The baseball think is perhaps as much as 10 years old now.
And the replacement of ads in movies already started. I think it was Turner who was holding up movie companies for extra dough to not replace their ads with other ads when they showed the movies on TV. I remember seeing a movie on TV with a scene in Times Square where they had replaced one ad with another.
The stuff about AMD's cpu bearing the weight of the DMA requests is really an issue as to whether the DMA requests are slowed down more than an issue of if the CPU would be slowed down by the DMA requests. The CPU would be slowed down by the DMA requests if it didn't have dedicated circuitry to handle it. But if course it does have the circuitry, it couldn't really afford not to. It does add additional complexity and power consumption to the chip though.
I agree Dish is good at brinksmanship. They've gone toe to toe with channels before and said "our customers may lose your channel, but you'll also lose our customers" (and the revenue that goes with them).
That works because the channel has those customers right now.
This is different. If Dish pulls that on TiVo, TiVo will simply respond "we don't have your customers (or their revenue) right now anyway, what exactly do we have to lose?"
I don't think this well-used Dish tactic will apply this time.
Bush has violated no rights of anybody in Git'mo. They are *not* US Citizens therefore they have no rights under the Constitution. They are enemy combatants. They do not even have rights under the Geneva convention since they operate under no recognized flag; They are terrorists. In effect, they are spy's and the Geneva Convention allows us to shoot them on sight... so I guess we are treating them better than they deserve, eh?
The Constutition says we are granted certain inalienable rights. It doesn't say that being in the United States gives you the rights, it says you have those rights and the citizens agree to grant certain priviliges to the government to help them own cause.
You have to remember the founding fathers had just finished fighting a war in a British colony (there was no USA) over thus stuff. And none of them were US citizens at the time because there was no US. Do you really think they were fighting for the time for something they felt they deserved at a later point in time once they made their own government up?
The Constitution doesn't give demarcation points beyond which rights don't exist.
Lastly, the decision this activist judge made only effects the Eastern District of Michigan. The rest of the country is unaffected by her ruling since it is outside her jurisdiction. All she has done is make her district a little less safe for US citizens and more of a safe-haven for Alqaeda.
That last part is ridiculous. But anyway, you need to look up how precedent works. The rulings of a US District judge set precedent for the entire country.
We have the swabbing system, the air puffer and neutron bombardment systems now.
He wouldn't get the nitrogen-based stuff through now.
Additionally, you'll note that he didn't bring down flight 434.
It'd still be easy to get the wire through. The current equipment and the current process (which is the important part) of screening is still mostly effective on larger lumps of metal than small threads. You'd take a risk now of being caught, but pretty damn small. As the Israelis point out, you're probably more at risk of the screener noticing you are extremely nervous than them noticing your wire (if you hid it correctly).
Macrovision would cause copies to exhibit a pulsing fade out. That is, on a copy the image would go from fully there to very dim (often colorless) and noisy, then fade back in.
This is because when the AGC is fooled into thinking the signal is stronger than it is, it attenuates the actual signal during recording, so it fades out.
Macrovision also has another protection that is used only on DVDs. This encoding puts an error in the color burst on each line. This encoding cannot be used on videotape, as VCRs cannot reproduce it. On DVDs, the framing portions of the video signal are created "on-the-fly", not just replayed from a recording and thus these errors can be put in.
Macrovision on DVDs is optional, the publisher of the DVD has to pay Macrovision a per-copy fee to activate it. Since all copying of DVDs now is done digitally at high speed instead of by recording the analog output of the DVD player, the value of Macrovision protection to the publisher is questionable. So many DVDs are now released without this protection.
The sync supression system described is the system that was used on cable (HBO) in the early analog days. It was used on some video recordings, but it caused compatibility problems and was not very effective at preventing copies, as it would require multiple generational copies before the desired reduction in video quality and stability really took effect.
If this injunction holds, TiVo will go after every company who makes DVRs. So EchoStar won't be any more disadvantaged than Comcast or DirecTV.
I don't really follow though how this is bad for TiVo. If they place the blame (wrongly) on TiVo, so what? Blame doesn't have a price, money does. If TiVo's IP means everyone who makes a DVR has to pay them a license fee, and customers demand DVRs, then that means that the cable companies and satellite companies are forced to pay TiVo to satisfy their customers. This is in no way bad for TiVo.
TiVo will offer EchoStar a licensing deal to keep the service on. So if it turns off in 30 days, it isn't TiVo punishing EchoStar customers, it is EchoStar doing so.
I'm not saying you're wrong. But "liquid" was perhaps the wrong term.
The question is whether undetectable, binary liquid bombs are feasible. To be undetectable, they couldn't be nitrogen-based explosives, as that is what all the detectors sniff for.
So the question is, could a two-part, non-Nitrogen-based liquid explosive (so called peroxide bombs) be smuggled onto a plane and then make a large enough explosion to bring it down?
It seems rather unlikely to me, with only a light skimming of the info. But I could easily be wrong. That's why I found the slashdot post interesting (although I didn't read the article, as I don't read the Register anymore due to rampant BS from them).
It baffles me that its become legendary, and that it appears to be common knowledge that it is key in AMD reducing latency.
But I can't figure out how it would do so. And the Core 2 Duos show Intel matching and besting AMD on latency. No cache can truly reduce latency (only mask it on hits), so it's pretty clear to me Intel has matched AMD's latency without an on-chip memory controller.
Also, Intel isn't brute-forcing the FSB with huge caches. The issue here is cache synchronization. AMD has HT to do this, and HT is fast and compact. It's so fast that it allows AMD's entire (excellent) NUMA system. AMD can use piecemeal portions of the L2 cache from one CPU as cache for the other CPU with little overhead (latency). And they can make their caches exclusive, so that the L2 doesn't uselessly overlap the L1.
Intel cannot do this. In the past, each cache was completely independent and the system kept them coherent with MERSI protocol and transactions over the FSB. Since the FSB is so slow, that slowed down each access to a non-exclusive (the E in MERSI) cache line while the core waits to see if anyone has a newer version of the active cache line in their cache. This undercuts the value of a cache, although most lines in the cache will be exclusive at any given time.
With the Core processors, since two cores are on one die, the cores communicate directly across the die to maintain cache coherency. This is similar to AMD's "crossbar switch" (a term almost never used properly) in the X2s. Additionally, Intel can adjust the split in their cache so that either core gets the entire cache (most useful when the other core is halted) or they both share it 50-50. This approximates the L2 sharing AMD gets from NUMA. It's more granular, but it's actually faster per transaction. One notable difference is Intel's system doesn't work across dice, which means that Intel's two die Kentsfield system will again suffer on non-exclusive pages. AMD's 4x4 will suffer vastly less (it can no longer use just the crossbar switch, but HT is still very efficient).
So Intel's caching is in my opinion not Intel brute forcing anything. They may not have a system as elegant as NUMA, but they have applied multiple valid techniques to produce a system that in the general case outperforms AMD's memory system.
Back to the on-chip memory controller, I've designed several very successful systems in the last few years. So successful that there's a 50% chance you own one of them! I'm not going to pretend the consumer products I did are in the same league as Core or Athlon in terms of memory bandwidth. But this experience has highlighted the issues of FSBs, cache coherency, DMA, and memory controllers.
In a system with cache coherency (PCs are cache coherent, as any high performance system must be), the cache controller(s) must see every memory access in the system (even DMAs). In an Intel, that means every memory access must appear on the FSB. Now, that may seem like an obvious statement, but since much of the DMA and the memory controllers both appear on the Northbridge (NB) in a PC, the NB could just route data directly from the DMA controller to the memory and back without putting anything on the FSB, except then the CPU's cache controller would become incoherent, which is bad. AMD puts the cache controller and the memory controller next to each other on one chip, so they can easily communicate (over HT, at least for coherency).
However, putting the memory controller on the CPU means every memory access not only has to be seen by the CPU, but processed by the CPU. DMA memory accesses instead of being send to the CPU for cache snooping instead have to go through the CPU for translation to memory signalling. That means you have to put a LOT of pins on the CPU. Especially in a system with dual-channel DDR2 SDRAM. And those transistors are working hard. This puts more heat into your CPU.
Also, according to common knowledge it increases the memory latency on DMAs. Except I dunno about that common knowledge
And it sill compile, run and happen. The number will appear to fit.
Except x doesn't hold precisely 16777215. It holds approximately 16777215. Yes, everyone should know that things like this can occur and program so they don't run into such problems. But the whole point of the article is people don't know this, and they don't program around such problems.
For example, double-precision reals can exactly represent all integers up to 2^53, and all even integers up to 2^54, and all integers divisible by four up to 2^55, etc. They can accurately represent cash values in pennies up to 8 trillion dollars (or 8 billion, if you want to count thousandths of a cent).
These statements are completely true. They also lose close to non-obvious problems like that even though it can exactly represent all integers up to 2^53, if the proper result for the formula you are computing is an integer up to 2^53, it doesn't mean the double that represents that result will equal that integer. Often it will be close to that integer within some error bars. You really should compute these error bars so you can then compare against the proper result or do a round to decimal place (in this case integer, the 0th decimal place) within these error bars against that value. But instead people do
if (81 == x)
and it doesn't match.
The IEEE standard does a great job with guard bits to attempt to prevent this, but in the end, it is up to the programmer to understand that precision will be lost (because floats are imprecise) and how to work around this.
Ask a programmer if they know floats are imprecise and they'll say they are and they are familiar with the issues. Then ask them if 0.1 can be accurately represented in a float and they'll look at you quizicaly as if the question were to trivial that it doesn't even need to be asked. When you point out it cannot, they'll maybe say something like "not my problem, I use doubles instead of floats anyway, they are more accurate".
It's a big problem. Floats are imprecise, they approximate values in situations people people don't expect. And because of that, at the end of a sequence of operations, they often end up with a messy 0.000000001 sticking on their "precise" integer less than 2^53 and they rarely investigate the proper way to handle it.
AMD has to change their socket all the time because they bring the memory bus to the socket. Want to go from DDR to DDR2? AMD has to change their socket. Want to go to FB-DIMMs? New socket.
Since the memory controller isn't on the CPU on Intel, that means they can keep the same socket longer. They do have to up the FSB speed from time to time (775 started at 800FSB, and is at 1333FSB now), but the socket didn't have to change.
To be honest, as the power spec to the CPU often gets tightened or increased with new chips anyway, you can't really use old mobos with new chips anyway. There were plenty of socket 939 mobos made that never could take an X2.
Kinda funny too that when X2 came out in the 939 socket, people were like "yeah, same socket, that's a good thing!", but when Core 2 Duo comes out in the same socket, some people instead say "same socket, that's a bad thing!"
Anyway, I'm sure you already know 775 isn't a PGA socket. It's an LGA, just like AMD just went to.
Intel's Kentsfield 4-core CPUs (two dice, two cores per die) fit in 775 just fine. Also their next 4-core CPU which uses 4 cores on one die will fit also. That's a lot of expansion capability.
Anyway, I don't mind buying new mobos, I usually buy the $400 version of a CPU, and so sporting $150 for a mobo too isn't something that bothers me. Old mobos don't necessarily provide max performance for the new chips anyway, even if they are compatible. I know others that don't have as much to spend would feel differently.
the best example I've seen of convergence...
on
Convergence Culture
·
· Score: 1
Is the cell phone and the wristwatch.
Young people often just don't wear watches. Everyone my age does (mid 30s), but younger people often don't because they always have their cell phone and are used to using that.
Some of these people will wear wristwatches for fashion later, but as functionality thing, the wristwatch is in steep market decline.
But in this case there's really no point to putting them in. This system works fine if someone doesn't go out of their way to defeat it. There's no reason to defeat it, as the parts are fed in an out by an automated picking system. The only time to approach the press is if it jams, and then you're gonna have to stop it to clear it anyway.
Since any system can be defeated, a system like this that requires defeating to create danger is as good as any.
These systems were in a pressed metal plant of a major auto manufacturer. They had enough labor problems that I'm sure OSHA was called on site at least 1 day a week.
My father's cousin (i.e. my first cousin once removed) lost one and a half fingers on one hand and three fingers on the other because he bypassed safety guards on a press (not in this plant, in another). The worst part is that it happened in two separate incidents. You just can't make anything foolproof because fools are so ingenious.
People use floats because they can hold "really big numbers". But they don't really hold the really big numbers, they just approximate them.
Floats are imprecise. They appear precise in ranges of represented values and for sizes of errors that people commonly use. But in actuality, they will silently use an approximation of the number you tried to put in instead of the real number if the number cannot be precisely represented.
That's why they are imprecise, and that's one of the big dangers.
I grew up in a manufacturing. The large presses were controlled by a panel with two large buttons on it. You had to press both buttons to run it. The panel was a safe distance away from the press. Since holding your hands on the buttons for 8 hours was tiresome, there were c-shaped pieces of metal above the buttons. So now you just put your hand between the metal and the button and the metal would hold your hand to the button, holding the button pressed as long as your hand was there. Of course, you could also wedge something in there instead. But there really was no reason to do so.
This plant was like this at least through the end of the 80s, and it was inspected constantly. It passed OSHA.
The number of people who really understand floats is less than 1% of the people who think they do.
Do you understand that
(A < B)
is not the same as
!(A >= B)
and that
((A + 1) == (A))
Can be true?
Every day, many people make the mistake of using floats when wat they really wanted was the ability just to represent large numbers. For example, in Mac OS X, the system uses doubles as representations of time. This is the worst idea I can think of. First of all, floats are imprecise and time is the thing that man can subdivide the most precisely. Secondly, if a Mac OS X machine is on long enough, time will cease to progress becuase of the 2nd statement above!
Plenty of people who thought they knew what they were doing have used floats in places where they are a bad idea. And it continues to today.
So I say no, Computer Science 101 doesn't seem to cover all you need to know about floats.
This article makes some sense. But when he tries to explain that it should trigger an GFCI (or even AFCI), he gets way off track.
It would never trigger an AFCI, because there's too much smoothing circuitry between the output and the wall plug. No matter, as an AFCI is designed to protect against arcs in the walls and frayed AC power cords. So the AFCI comment didn't make sense.
Also, the GFCI comment doesn't make sense either. A GFCI is supposed to notice power being drawn and not returned on the neutral. The Apple power supplies are designed to be 2-prong devices, so they could never dump significant power on the ground pin and trigger a GFCI. The only way it could trigger a GFCI is if you shorted the live end of the cable to a separate return, like earth ground or a hot tub or whatever. Then the power would not come back on the neutral and would trigger the GFCI.
Anyway, a GFCI is supposed to prevent against things like dropping a live appliance into a puddle of water or whatever, not shorts internal to low voltage cables.
His spark test maybe means something, I see what he is talking about there. But I'm not sure about his testing methodology. Maybe he's testing a case expecting it to shut down and instead Apple just current limits, which is an acceptable alternative. I just can't tell with only the data on that page.
The article summary is definitely full of unwarranted hyperbole. The article isn't even close to triggering a level of "source of some serious safety concerns".
I am just reminding you that being closed-minded makes you look like an ass. Note that I am not calling you an ass... just that making over-broad statements makes you look like one. You ought to remember as you write that you might be wrong instead of getting too wrapped up in your conclusion that others are wrong.
No, you're being an ass. It takes two sides to have a disagreement, you have no room to stand on a pedestal here.
No. Rectification is not necessarily 97%... it is only that efficient when modern active rectification is used... so I would expect significant savings over cheaper, smaller power supplies. The savings occurs because a) they distribute higher voltage than the typical 120VAc, and b) they eliminate the less-efficient rectification stage that occurs inside the individual smaller computer power supplies. So 97% leaves plenty of room for improvement if a couple of 90% efficient stages can be bypassed. However, on this note I will sign off, because while I can see possible avenues for energy savings in this experiment, I don't know the details of why this demo achieved the results they claim.
Fine then. In that case, the study would be rigged. It would be trying to show that using DC is 15% more efficient, ignoring that a simple change to power supplies with better rectification and 240V (which is easily generated by a UPS and would be accepted by any decent power supply, especially ones that already spent the money for good rectification) would give you 80% of the gain (a 12% boost) without all the trouble.
So now a company with efficiency in mind doesn't need to arrange DC power to their data center. They don't even need to rewire it. Now they just need to spec efficient, 240V capable power supplies in their servers. That's a lot simpler. But I suppose that wouldn't grab the headlines.
At some draws, the power supply uses fixed (inaudible) frequencies. At moderate draws, it can switch between the two modes. At lower draws, it uses PFM mode. At these draws, the amount of current drawn determines the frequency.
At high draws, no noise, as it is operating at an ultrasonic frequency. At low draws, no noise, as it is operating at a low frequency that your ear isn't sensitive to and the total energy in the noise is lower as less power is going through the coil.
As you pass through a certain range of current draw, it produces the chirp.
Your argument that it's the sleep mode Apple picked and not coil buzz is ridiculous. In which modes exactly does a chip make noise? Where's the speaker (or other transducer) on the chip? An inductor is a wound coil, just like you use in a dynamic (regular) speaker, which is why it is prone to making noise. Chips do not make noise. There is another way for switching power supply noise to become audible though. I know it. Do you?
Yes, it seems Apple could have turned of the power to one core and have avoided most of the noise. But turning the cores on and off on the fly is impractical. It can be done, but not fast enough to get you the dual-core performance you paid for. You end up unable to utilize the second core well.
My AMD X2 4200+ has massive power savings modes, it changes its voltage from 1.1V to 1.4V, it changes its speed from 1GHz to 2.2GHz. But it never actually turns one core off either.
If Apple is lazy, everyone is lazy, and perhaps you should get off your lazy ass and show them how it is done.
Instead, Apple could redesign the power supply so that in normal operation it doesn't pass through the audible range. This involves other tradeoffs, and it isn't simple. But it's better than wasting power or robbing you of CPU by choosing other power modes or making one core unavailable.
This still doesn't keep the coils from moving completely, but it does help.
If the coils are currently too loose, then adding superglue can help make it quieter. If they're already glued well, it won't help.
It kinds of depends. Are the coils glued less than they should be? Or is there just too much flux through them so that even glued they vibrate too much?
If it's not 100% native, what would have to be changed to make it 100% native?
I do hear some operations are slower (can't tell if it's just a rumor though), but that doesn't make it not 100% native.
If you say AMD doesn't slow down to run 64-bit code unlike Intel, perhaps you're just thinking of it the wrong way. Maybe both AMD and Intel are 100% 64-bit native but AMD is only 80% 32-bit native? Thus the Intel runs 32-bit code much faster than the AMD, but 64-bit somewhat less faster.
I can get a 4GB MS Pro Duo stick right now from Buy.com for $100. Why would I want a spinning, fragile, unreplaceable media when I can get solid state storage in a slot instead? I can stick that Pro Duo stick in my Sony W810i and play the music off it. The music UI on the W810i is better than that on the N91, although both can use a little work. And the W810i battery will play for about 25 hours, the N91 goes 10. The W810i lets you use your own earbuds through a clever microphone yoke, the N91 has wired-in earbuds on its special headset.
Nokia diddled around too long, the N91 was pointless before it ever came out.
But if what the know is what you know, then no one really knows.
The problem is plain and simply coil buzz.
Laptops use switching power supplies, because linear ones aren't efficient enough. Switching power supplies use wire wound inductors to store energy while converted it from one voltage to another. These switching power supplies are constantly filled and emptied of energy. This often causes the coils to vibrate slightly. It's the same thing you hear from a power substation, only in a power substation it is at a fixed 60Hz as the coils in the transformers constantly empty and fill as the AC voltage dips above and below 0V.
In a laptop, the frequency depends on the switching power supply design. There are fixed-frequency switching power supplies, but these are not efficient across a wide range of power draws. So they have to use a variable frequency switching power supply. The problem is that the frequency ranges the power supply uses include the range 300Hz-3KHz, where the ear is very sensitive to the buzz.
When the power draw is high, the frequency is high, when it goes down, the frequency drops. If the frequency sweeps through the audible range, you hear chirps, like the G5 towers exhibited or moos (although the moos are often a 2nd order effect). If the frequency stops in the audible range, you hear a whine, like the laptops can show.
If you modify the power settings to keep the power supply outside the audible range, then you either limit your CPU speed (by going single core) or significantly increased your power draw (by turning off CPU napping). There is another whine which comes from the backlight power supply, it will also change frequency (to often be inaudible) if you change the backlight to be higher or lower.
Apple didn't pick the wrong mode, they need to go to that mode to save power and reduce heat.
Apple should do everything the can to reduce the whines. But it's not practical to remove it completely.
"To be positive is to be wrong at the top of your lungs." - wow, what an ass you are.
The test obtained 15% at the facility level.
The test could be 15% at the facility level if they considered the facility to receive DC power and still be subject to the caveats I mention. This is unrealistic today, but it might be in their assumptions since they want to prove that a major change should be effected . Saying "facility level" does not negate what I said.
The test was conducted in the U.S.
This means nothing. They are trying to explain how major-level plant changes can be effective in helping efficiency. There's no reason to precluse the idea of using UK-style 240V AC if that would make it more efficient.
It is not a stretch to assume that their power-factor-correcting 480VAC input facility UPSs have 380VDC internally.
Actually, 480VAC input facilities have greater than 380VDC internally, guaranteed. I didn't think 480 or 440VAC facilities were a large enough part of the market to care about (figured 208VAC was more common), but it appears I am wrong about that.
No, they are aware that the same active rectification that is so popular with variable speed drives (electric motors) due to good power factor can achieve 97% efficiency.
If rectification (and inversion) were 97% efficient (and perhaps it is), then there would be no way to save 15% on your power used, and switching to DC would be near pointless. Want to modify your statement?
Honestly, if all you want to do is raise the efficiency from your UPS to the racks, then either rig it to output UK-style 240V AC or 3-phase AC. Better yet, get inside and turn off the inverter so it generates 240V rectified AC (lumpy DC). You won't even have to modify the equipment in your racks, and you should save on inversion losses. Next step would be to turn off the sine wave shaper in your racks, your equipment probably would still survive. Best to leave in short 0 pulses from time to time or you may find that you are unable to soft-off your equipment due to the Triacs inside never shutting off.
You're essentially outputting unregulated high voltage DC now, perhaps with gaps in it. You'll save some money I suppose, something is better than nothing.
Slashdot Mirror
Except you're years behind.
The baseball think is perhaps as much as 10 years old now.
And the replacement of ads in movies already started. I think it was Turner who was holding up movie companies for extra dough to not replace their ads with other ads when they showed the movies on TV. I remember seeing a movie on TV with a scene in Times Square where they had replaced one ad with another.
The stuff about AMD's cpu bearing the weight of the DMA requests is really an issue as to whether the DMA requests are slowed down more than an issue of if the CPU would be slowed down by the DMA requests. The CPU would be slowed down by the DMA requests if it didn't have dedicated circuitry to handle it. But if course it does have the circuitry, it couldn't really afford not to. It does add additional complexity and power consumption to the chip though.
I agree Dish is good at brinksmanship. They've gone toe to toe with channels before and said "our customers may lose your channel, but you'll also lose our customers" (and the revenue that goes with them).
That works because the channel has those customers right now.
This is different. If Dish pulls that on TiVo, TiVo will simply respond "we don't have your customers (or their revenue) right now anyway, what exactly do we have to lose?"
I don't think this well-used Dish tactic will apply this time.
Bush has violated no rights of anybody in Git'mo. They are *not* US Citizens therefore they have no rights under the Constitution. They are enemy combatants. They do not even have rights under the Geneva convention since they operate under no recognized flag; They are terrorists. In effect, they are spy's and the Geneva Convention allows us to shoot them on sight... so I guess we are treating them better than they deserve, eh?
The Constutition says we are granted certain inalienable rights. It doesn't say that being in the United States gives you the rights, it says you have those rights and the citizens agree to grant certain priviliges to the government to help them own cause.
You have to remember the founding fathers had just finished fighting a war in a British colony (there was no USA) over thus stuff. And none of them were US citizens at the time because there was no US. Do you really think they were fighting for the time for something they felt they deserved at a later point in time once they made their own government up?
The Constitution doesn't give demarcation points beyond which rights don't exist.
Lastly, the decision this activist judge made only effects the Eastern District of Michigan. The rest of the country is unaffected by her ruling since it is outside her jurisdiction. All she has done is make her district a little less safe for US citizens and more of a safe-haven for Alqaeda.
That last part is ridiculous. But anyway, you need to look up how precedent works. The rulings of a US District judge set precedent for the entire country.
We have the swabbing system, the air puffer and neutron bombardment systems now.
He wouldn't get the nitrogen-based stuff through now.
Additionally, you'll note that he didn't bring down flight 434.
It'd still be easy to get the wire through. The current equipment and the current process (which is the important part) of screening is still mostly effective on larger lumps of metal than small threads. You'd take a risk now of being caught, but pretty damn small. As the Israelis point out, you're probably more at risk of the screener noticing you are extremely nervous than them noticing your wire (if you hid it correctly).
Macrovision would cause copies to exhibit a pulsing fade out. That is, on a copy the image would go from fully there to very dim (often colorless) and noisy, then fade back in.
This is because when the AGC is fooled into thinking the signal is stronger than it is, it attenuates the actual signal during recording, so it fades out.
Macrovision also has another protection that is used only on DVDs. This encoding puts an error in the color burst on each line. This encoding cannot be used on videotape, as VCRs cannot reproduce it. On DVDs, the framing portions of the video signal are created "on-the-fly", not just replayed from a recording and thus these errors can be put in.
Macrovision on DVDs is optional, the publisher of the DVD has to pay Macrovision a per-copy fee to activate it. Since all copying of DVDs now is done digitally at high speed instead of by recording the analog output of the DVD player, the value of Macrovision protection to the publisher is questionable. So many DVDs are now released without this protection.
The sync supression system described is the system that was used on cable (HBO) in the early analog days. It was used on some video recordings, but it caused compatibility problems and was not very effective at preventing copies, as it would require multiple generational copies before the desired reduction in video quality and stability really took effect.
If this injunction holds, TiVo will go after every company who makes DVRs. So EchoStar won't be any more disadvantaged than Comcast or DirecTV.
I don't really follow though how this is bad for TiVo. If they place the blame (wrongly) on TiVo, so what? Blame doesn't have a price, money does. If TiVo's IP means everyone who makes a DVR has to pay them a license fee, and customers demand DVRs, then that means that the cable companies and satellite companies are forced to pay TiVo to satisfy their customers. This is in no way bad for TiVo.
TiVo will offer EchoStar a licensing deal to keep the service on. So if it turns off in 30 days, it isn't TiVo punishing EchoStar customers, it is EchoStar doing so.
I'm sorry, what is it going to challenge the 770 at?
The 770 is crap. Generally you don't compete to see who can be the worst piece of crap.
(yes, I've used it, had one for a couple days.)
I'm not saying you're wrong. But "liquid" was perhaps the wrong term.
The question is whether undetectable, binary liquid bombs are feasible. To be undetectable, they couldn't be nitrogen-based explosives, as that is what all the detectors sniff for.
So the question is, could a two-part, non-Nitrogen-based liquid explosive (so called peroxide bombs) be smuggled onto a plane and then make a large enough explosion to bring it down?
It seems rather unlikely to me, with only a light skimming of the info. But I could easily be wrong. That's why I found the slashdot post interesting (although I didn't read the article, as I don't read the Register anymore due to rampant BS from them).
It baffles me that its become legendary, and that it appears to be common knowledge that it is key in AMD reducing latency.
But I can't figure out how it would do so. And the Core 2 Duos show Intel matching and besting AMD on latency. No cache can truly reduce latency (only mask it on hits), so it's pretty clear to me Intel has matched AMD's latency without an on-chip memory controller.
Also, Intel isn't brute-forcing the FSB with huge caches. The issue here is cache synchronization. AMD has HT to do this, and HT is fast and compact. It's so fast that it allows AMD's entire (excellent) NUMA system. AMD can use piecemeal portions of the L2 cache from one CPU as cache for the other CPU with little overhead (latency). And they can make their caches exclusive, so that the L2 doesn't uselessly overlap the L1.
Intel cannot do this. In the past, each cache was completely independent and the system kept them coherent with MERSI protocol and transactions over the FSB. Since the FSB is so slow, that slowed down each access to a non-exclusive (the E in MERSI) cache line while the core waits to see if anyone has a newer version of the active cache line in their cache. This undercuts the value of a cache, although most lines in the cache will be exclusive at any given time.
With the Core processors, since two cores are on one die, the cores communicate directly across the die to maintain cache coherency. This is similar to AMD's "crossbar switch" (a term almost never used properly) in the X2s. Additionally, Intel can adjust the split in their cache so that either core gets the entire cache (most useful when the other core is halted) or they both share it 50-50. This approximates the L2 sharing AMD gets from NUMA. It's more granular, but it's actually faster per transaction. One notable difference is Intel's system doesn't work across dice, which means that Intel's two die Kentsfield system will again suffer on non-exclusive pages. AMD's 4x4 will suffer vastly less (it can no longer use just the crossbar switch, but HT is still very efficient).
So Intel's caching is in my opinion not Intel brute forcing anything. They may not have a system as elegant as NUMA, but they have applied multiple valid techniques to produce a system that in the general case outperforms AMD's memory system.
Back to the on-chip memory controller, I've designed several very successful systems in the last few years. So successful that there's a 50% chance you own one of them! I'm not going to pretend the consumer products I did are in the same league as Core or Athlon in terms of memory bandwidth. But this experience has highlighted the issues of FSBs, cache coherency, DMA, and memory controllers.
In a system with cache coherency (PCs are cache coherent, as any high performance system must be), the cache controller(s) must see every memory access in the system (even DMAs). In an Intel, that means every memory access must appear on the FSB. Now, that may seem like an obvious statement, but since much of the DMA and the memory controllers both appear on the Northbridge (NB) in a PC, the NB could just route data directly from the DMA controller to the memory and back without putting anything on the FSB, except then the CPU's cache controller would become incoherent, which is bad. AMD puts the cache controller and the memory controller next to each other on one chip, so they can easily communicate (over HT, at least for coherency).
However, putting the memory controller on the CPU means every memory access not only has to be seen by the CPU, but processed by the CPU. DMA memory accesses instead of being send to the CPU for cache snooping instead have to go through the CPU for translation to memory signalling. That means you have to put a LOT of pins on the CPU. Especially in a system with dual-channel DDR2 SDRAM. And those transistors are working hard. This puts more heat into your CPU.
Also, according to common knowledge it increases the memory latency on DMAs. Except I dunno about that common knowledge
Floats are imprecise.
You can do this statement:
x = (float) 16777215
And it sill compile, run and happen. The number will appear to fit.
Except x doesn't hold precisely 16777215. It holds approximately 16777215. Yes, everyone should know that things like this can occur and program so they don't run into such problems. But the whole point of the article is people don't know this, and they don't program around such problems.
For example, double-precision reals can exactly represent all integers up to 2^53, and all even integers up to 2^54, and all integers divisible by four up to 2^55, etc.
They can accurately represent cash values in pennies up to 8 trillion dollars (or 8 billion, if you want to count thousandths of a cent).
These statements are completely true. They also lose close to non-obvious problems like that even though it can exactly represent all integers up to 2^53, if the proper result for the formula you are computing is an integer up to 2^53, it doesn't mean the double that represents that result will equal that integer. Often it will be close to that integer within some error bars. You really should compute these error bars so you can then compare against the proper result or do a round to decimal place (in this case integer, the 0th decimal place) within these error bars against that value. But instead people do
if (81 == x)
and it doesn't match.
The IEEE standard does a great job with guard bits to attempt to prevent this, but in the end, it is up to the programmer to understand that precision will be lost (because floats are imprecise) and how to work around this.
Ask a programmer if they know floats are imprecise and they'll say they are and they are familiar with the issues. Then ask them if 0.1 can be accurately represented in a float and they'll look at you quizicaly as if the question were to trivial that it doesn't even need to be asked. When you point out it cannot, they'll maybe say something like "not my problem, I use doubles instead of floats anyway, they are more accurate".
It's a big problem. Floats are imprecise, they approximate values in situations people people don't expect. And because of that, at the end of a sequence of operations, they often end up with a messy 0.000000001 sticking on their "precise" integer less than 2^53 and they rarely investigate the proper way to handle it.
AMD has to change their socket all the time because they bring the memory bus to the socket. Want to go from DDR to DDR2? AMD has to change their socket. Want to go to FB-DIMMs? New socket.
Since the memory controller isn't on the CPU on Intel, that means they can keep the same socket longer. They do have to up the FSB speed from time to time (775 started at 800FSB, and is at 1333FSB now), but the socket didn't have to change.
To be honest, as the power spec to the CPU often gets tightened or increased with new chips anyway, you can't really use old mobos with new chips anyway. There were plenty of socket 939 mobos made that never could take an X2.
Kinda funny too that when X2 came out in the 939 socket, people were like "yeah, same socket, that's a good thing!", but when Core 2 Duo comes out in the same socket, some people instead say "same socket, that's a bad thing!"
Anyway, I'm sure you already know 775 isn't a PGA socket. It's an LGA, just like AMD just went to.
Intel's Kentsfield 4-core CPUs (two dice, two cores per die) fit in 775 just fine. Also their next 4-core CPU which uses 4 cores on one die will fit also. That's a lot of expansion capability.
Anyway, I don't mind buying new mobos, I usually buy the $400 version of a CPU, and so sporting $150 for a mobo too isn't something that bothers me. Old mobos don't necessarily provide max performance for the new chips anyway, even if they are compatible. I know others that don't have as much to spend would feel differently.
Is the cell phone and the wristwatch.
Young people often just don't wear watches. Everyone my age does (mid 30s), but younger people often don't because they always have their cell phone and are used to using that.
Some of these people will wear wristwatches for fashion later, but as functionality thing, the wristwatch is in steep market decline.
But in this case there's really no point to putting them in. This system works fine if someone doesn't go out of their way to defeat it. There's no reason to defeat it, as the parts are fed in an out by an automated picking system. The only time to approach the press is if it jams, and then you're gonna have to stop it to clear it anyway.
Since any system can be defeated, a system like this that requires defeating to create danger is as good as any.
These systems were in a pressed metal plant of a major auto manufacturer. They had enough labor problems that I'm sure OSHA was called on site at least 1 day a week.
My father's cousin (i.e. my first cousin once removed) lost one and a half fingers on one hand and three fingers on the other because he bypassed safety guards on a press (not in this plant, in another). The worst part is that it happened in two separate incidents. You just can't make anything foolproof because fools are so ingenious.
People use floats because they can hold "really big numbers". But they don't really hold the really big numbers, they just approximate them.
Floats are imprecise. They appear precise in ranges of represented values and for sizes of errors that people commonly use. But in actuality, they will silently use an approximation of the number you tried to put in instead of the real number if the number cannot be precisely represented.
That's why they are imprecise, and that's one of the big dangers.
I grew up in a manufacturing. The large presses were controlled by a panel with two large buttons on it. You had to press both buttons to run it. The panel was a safe distance away from the press. Since holding your hands on the buttons for 8 hours was tiresome, there were c-shaped pieces of metal above the buttons. So now you just put your hand between the metal and the button and the metal would hold your hand to the button, holding the button pressed as long as your hand was there. Of course, you could also wedge something in there instead. But there really was no reason to do so.
This plant was like this at least through the end of the 80s, and it was inspected constantly. It passed OSHA.
Do you understand thatis not the same asand thatCan be true?
Every day, many people make the mistake of using floats when wat they really wanted was the ability just to represent large numbers. For example, in Mac OS X, the system uses doubles as representations of time. This is the worst idea I can think of. First of all, floats are imprecise and time is the thing that man can subdivide the most precisely. Secondly, if a Mac OS X machine is on long enough, time will cease to progress becuase of the 2nd statement above!
Plenty of people who thought they knew what they were doing have used floats in places where they are a bad idea. And it continues to today.
So I say no, Computer Science 101 doesn't seem to cover all you need to know about floats.
This article makes some sense. But when he tries to explain that it should trigger an GFCI (or even AFCI), he gets way off track.
It would never trigger an AFCI, because there's too much smoothing circuitry between the output and the wall plug. No matter, as an AFCI is designed to protect against arcs in the walls and frayed AC power cords. So the AFCI comment didn't make sense.
Also, the GFCI comment doesn't make sense either. A GFCI is supposed to notice power being drawn and not returned on the neutral. The Apple power supplies are designed to be 2-prong devices, so they could never dump significant power on the ground pin and trigger a GFCI. The only way it could trigger a GFCI is if you shorted the live end of the cable to a separate return, like earth ground or a hot tub or whatever. Then the power would not come back on the neutral and would trigger the GFCI.
Anyway, a GFCI is supposed to prevent against things like dropping a live appliance into a puddle of water or whatever, not shorts internal to low voltage cables.
His spark test maybe means something, I see what he is talking about there. But I'm not sure about his testing methodology. Maybe he's testing a case expecting it to shut down and instead Apple just current limits, which is an acceptable alternative. I just can't tell with only the data on that page.
The article summary is definitely full of unwarranted hyperbole. The article isn't even close to triggering a level of "source of some serious safety concerns".
I am just reminding you that being closed-minded makes you look like an ass.
Note that I am not calling you an ass... just that making over-broad statements makes you look like one. You ought to remember as you write that you might be wrong instead of getting too wrapped up in your conclusion that others are wrong.
No, you're being an ass. It takes two sides to have a disagreement, you have no room to stand on a pedestal here.
No. Rectification is not necessarily 97%... it is only that efficient when modern active rectification is used... so I would expect significant savings over cheaper, smaller power supplies. The savings occurs because a) they distribute higher voltage than the typical 120VAc, and b) they eliminate the less-efficient rectification stage that occurs inside the individual smaller computer power supplies. So 97% leaves plenty of room for improvement if a couple of 90% efficient stages can be bypassed.
However, on this note I will sign off, because while I can see possible avenues for energy savings in this experiment, I don't know the details of why this demo achieved the results they claim.
Fine then. In that case, the study would be rigged. It would be trying to show that using DC is 15% more efficient, ignoring that a simple change to power supplies with better rectification and 240V (which is easily generated by a UPS and would be accepted by any decent power supply, especially ones that already spent the money for good rectification) would give you 80% of the gain (a 12% boost) without all the trouble.
So now a company with efficiency in mind doesn't need to arrange DC power to their data center. They don't even need to rewire it. Now they just need to spec efficient, 240V capable power supplies in their servers. That's a lot simpler. But I suppose that wouldn't grab the headlines.
Again, it all depends on the power draw.
At some draws, the power supply uses fixed (inaudible) frequencies.
At moderate draws, it can switch between the two modes.
At lower draws, it uses PFM mode. At these draws, the amount of current drawn determines the frequency.
At high draws, no noise, as it is operating at an ultrasonic frequency.
At low draws, no noise, as it is operating at a low frequency that your ear isn't sensitive to and the total energy in the noise is lower as less power is going through the coil.
As you pass through a certain range of current draw, it produces the chirp.
Your argument that it's the sleep mode Apple picked and not coil buzz is ridiculous. In which modes exactly does a chip make noise? Where's the speaker (or other transducer) on the chip? An inductor is a wound coil, just like you use in a dynamic (regular) speaker, which is why it is prone to making noise. Chips do not make noise. There is another way for switching power supply noise to become audible though. I know it. Do you?
Yes, it seems Apple could have turned of the power to one core and have avoided most of the noise. But turning the cores on and off on the fly is impractical. It can be done, but not fast enough to get you the dual-core performance you paid for. You end up unable to utilize the second core well.
My AMD X2 4200+ has massive power savings modes, it changes its voltage from 1.1V to 1.4V, it changes its speed from 1GHz to 2.2GHz. But it never actually turns one core off either.
If Apple is lazy, everyone is lazy, and perhaps you should get off your lazy ass and show them how it is done.
Instead, Apple could redesign the power supply so that in normal operation it doesn't pass through the audible range. This involves other tradeoffs, and it isn't simple. But it's better than wasting power or robbing you of CPU by choosing other power modes or making one core unavailable.
You buy the coils preglued.
This still doesn't keep the coils from moving completely, but it does help.
If the coils are currently too loose, then adding superglue can help make it quieter. If they're already glued well, it won't help.
It kinds of depends. Are the coils glued less than they should be? Or is there just too much flux through them so that even glued they vibrate too much?
If it's not 100% native, what would have to be changed to make it 100% native?
I do hear some operations are slower (can't tell if it's just a rumor though), but that doesn't make it not 100% native.
If you say AMD doesn't slow down to run 64-bit code unlike Intel, perhaps you're just thinking of it the wrong way. Maybe both AMD and Intel are 100% 64-bit native but AMD is only 80% 32-bit native? Thus the Intel runs 32-bit code much faster than the AMD, but 64-bit somewhat less faster.
A 4GB drive?
I can get a 4GB MS Pro Duo stick right now from Buy.com for $100. Why would I want a spinning, fragile, unreplaceable media when I can get solid state storage in a slot instead? I can stick that Pro Duo stick in my Sony W810i and play the music off it. The music UI on the W810i is better than that on the N91, although both can use a little work. And the W810i battery will play for about 25 hours, the N91 goes 10. The W810i lets you use your own earbuds through a clever microphone yoke, the N91 has wired-in earbuds on its special headset.
Nokia diddled around too long, the N91 was pointless before it ever came out.
But if what the know is what you know, then no one really knows.
The problem is plain and simply coil buzz.
Laptops use switching power supplies, because linear ones aren't efficient enough. Switching power supplies use wire wound inductors to store energy while converted it from one voltage to another. These switching power supplies are constantly filled and emptied of energy. This often causes the coils to vibrate slightly. It's the same thing you hear from a power substation, only in a power substation it is at a fixed 60Hz as the coils in the transformers constantly empty and fill as the AC voltage dips above and below 0V.
In a laptop, the frequency depends on the switching power supply design. There are fixed-frequency switching power supplies, but these are not efficient across a wide range of power draws. So they have to use a variable frequency switching power supply. The problem is that the frequency ranges the power supply uses include the range 300Hz-3KHz, where the ear is very sensitive to the buzz.
When the power draw is high, the frequency is high, when it goes down, the frequency drops. If the frequency sweeps through the audible range, you hear chirps, like the G5 towers exhibited or moos (although the moos are often a 2nd order effect). If the frequency stops in the audible range, you hear a whine, like the laptops can show.
If you modify the power settings to keep the power supply outside the audible range, then you either limit your CPU speed (by going single core) or significantly increased your power draw (by turning off CPU napping). There is another whine which comes from the backlight power supply, it will also change frequency (to often be inaudible) if you change the backlight to be higher or lower.
Apple didn't pick the wrong mode, they need to go to that mode to save power and reduce heat.
Apple should do everything the can to reduce the whines. But it's not practical to remove it completely.
"To be positive is to be wrong at the top of your lungs." - wow, what an ass you are.
The test obtained 15% at the facility level.
The test could be 15% at the facility level if they considered the facility to receive DC power and still be subject to the caveats I mention. This is unrealistic today, but it might be in their assumptions since they want to prove that a major change should be effected . Saying "facility level" does not negate what I said.
The test was conducted in the U.S.
This means nothing. They are trying to explain how major-level plant changes can be effective in helping efficiency. There's no reason to precluse the idea of using UK-style 240V AC if that would make it more efficient.
It is not a stretch to assume that their power-factor-correcting 480VAC input facility UPSs have 380VDC internally.
Actually, 480VAC input facilities have greater than 380VDC internally, guaranteed. I didn't think 480 or 440VAC facilities were a large enough part of the market to care about (figured 208VAC was more common), but it appears I am wrong about that.
No, they are aware that the same active rectification that is so popular with variable speed drives (electric motors) due to good power factor can achieve 97% efficiency.
If rectification (and inversion) were 97% efficient (and perhaps it is), then there would be no way to save 15% on your power used, and switching to DC would be near pointless. Want to modify your statement?
Honestly, if all you want to do is raise the efficiency from your UPS to the racks, then either rig it to output UK-style 240V AC or 3-phase AC. Better yet, get inside and turn off the inverter so it generates 240V rectified AC (lumpy DC). You won't even have to modify the equipment in your racks, and you should save on inversion losses. Next step would be to turn off the sine wave shaper in your racks, your equipment probably would still survive. Best to leave in short 0 pulses from time to time or you may find that you are unable to soft-off your equipment due to the Triacs inside never shutting off.
You're essentially outputting unregulated high voltage DC now, perhaps with gaps in it. You'll save some money I suppose, something is better than nothing.