It provides minimal advantages (mainly battery backup) over simply increasing system RAM. For 90% of people it makes more sense to increase system RAM.
Now if that drive used an older memory technology that was much cheaper per megabyte than modern system RAM, it would kick ass. Unfortunately, you need to load it with the same stuff you put into your system, and unless you need the battery backup, you'll get much more performance by simply sticking the memory into your system itself.
When accessing large files (not much seeking involved), modern hard drives have around double the sustained read/write speeds as that drive has CACHED read/write speeds. That thing's sustained write is only 1 MB/sec and its sustained read is only 2.3 MB/sec - even under incredibly heavy seeking, a decent SATA drive won't drop anywhere nearly that low.
That disadvantage of FAT causes excessive seeking on mechanical HDs.
It's not a problem with flash. Flash seeks instantly and the amount of data that actually needs to be written to the FAT is miniscule. I'd estimate less than 5% overhead at worst, most likely much less for large files.
Simply put, the raw write speeds of flash memory are LOW. Flash is slow as hell when you want to write to it. They've made huge advances in read speeds, but not write speeds.
Flash memory has slooooooooooooooow write speeds. Far slower than the hard drives' read speeds.
Battery-backed DRAM or SRAM would be a whole other story... Even slow DRAM that is a few generations behind current technology would provide an insane performance boost if used as a drive cache.
To avoid the nitpickers next time, you might want to say "solid-state nonvolatile memory is slow", since even though I'm sure you meant nonvolatile memory such as flash, everyone thought you were lumping in volatile memory (DRAM, SRAM).
It's too bad drives based on volatile memory died out. There are always 1-2 models available, but they invariably use the latest and greatest memory, which is expensive.
It would be nice to be able to mix memory types in a system - Have 512M-1 gig of the highest quality superfast stuff, but then also have even more older and slower memory. (In essence, adding another level of caching). A system with 256M of PC3200 and 4 gigs of memory running at a speed equal to PC100 would most likely blow away a system with 1 gig of PC3200 in memory-intensive applications. (Yes, I know that right now, older memory is more expensive per megabyte than newer stuff due to economies of scale, but if the demand for older memory were much greater, there would be production of the older stuff at rock-bottom prices.) If flash memory can reach prices below $50/gig, older DRAM technologies should be able to achieve half that in volume.
As to flash memory - It's going to replace hard drives in some niches (it already has) where the storage required will likely not go up much from current requirements. (Automotive navigation systems for example - there's not much data you can add beyond what is already required. Compared to a good street database, POI databases are tiny and that's about all they can add.) It's never going to replace hard drives in most places HDs are used. Just like everything else in computing, new applications arise to take advantage of advances in technology (Examples - media servers where someone's entire DVD collection is stored on hard drives rather than DVDs for convenience of access.) See one of the first poster's comments about this guy clearly having no knowledge of BitTorrent.:)
Also, like you said, flash memory is slow. To those who mention the existence of 150X and higher SD media - Keep in mind those are absolute maximum ratings. Read speeds can easily go that high, but write speeds of almost all nonvolatile solid-state memory technologies are waaaay behind their read speeds (except for flash cards with very low read speeds - read speeds keep improving but write speeds haven't improved that much), or even the read/write speeds of hard drives. There is research being done into nonvolatile memory with high write speeds such as phase change memory devices, but those are still in labs and years away from the market.
99% of legit or semi-legit HD content isn't going to be in MPEG4 AVC. It's going to be MPEG-2 Main Profile @ High Level (MP@HL) obtained from: An ATSC OTA HD tuner in the US A DVB tuner in Europe A QAM cable tuner for unencrypted US cable channels (There are more of these than you may think) Firewire from a cable or satellite box
No one uses MPEG4 for HD content unless they are archiving stuff that was originally obtained as MPEG-2 at a lower bitrate. It is most definately not currently available from more than a tiny handful of legitimate sources, if any. Any modern machine is more than capable of decoding 1080i MPEG-2, which is why it's now nearly impossible to buy HD tuner cards that do hardware decoding nowadays (whereas around 2 years ago, there was one HD tuner card that relied on software decoding and at least 5-6 ATSC cards that did HW decoding.)
The part of a machine that gets upgraded/replaced most often these days is the video card, since new generations are released an average of every 6 months, and unlike with most other improvements in PC capabilities (especially CPU), the applications take advantage of the new features and capabilities almost immediately. (Many games nowadays are released with graphics quality options that will make the game unacceptably slow on any current hardware, in order to allow the game to "grow" with new graphics cards that make those quality options not kill performance. One example is Doom 3's highest texture quality, which required a 512M video card - almost none existed at Doom 3's release, and very few exist even now. A few years from now 512 will probably become the norm.)
As a result, even if AMD changes socket types soon, it doesn't matter that much since the CPU is likely the last thing the OP will want to upgrade in the new system he buys. I don't think I've ever upgraded a CPU without getting a new motherboard, and I go MUCH longer between CPU upgrades than video card upgrades.
As to reccomendations - I think the original article poster is probably being paranoid about compatibility problems. As long as you stick with reputable motherboard and memory vendors, such problems are rare. I can only think of one such problem with one model of motherboard and a particular memory configuration, I don't even remember WHICH mobo that was though. (It was an older Athlon XP AGP board though.) Go to NewEgg, browse around, and read the customer reviews.:)
As to video card, I'd personally stick with NVidia rather than ATI. Even when ATI was well ahead of NV in performance, their drivers were so shoddy (especially in Linux, but their Windows drivers are horrifically inconsistent too) that buying ATI was like putting a V8 into a Yugo - wicked fast until you crash and burn. The one place I still hear compatibility horror stories is with ATI drivers - Game X works with ATI drivers older than version A, while Game Y requires drivers newer than version B which is higher than A. (Hasn't ATI ever heard of regression testing?) As a result I know multiple people who had to switch driver versions on a regular basis depending on which game they were playing. I've NEVER had to revert to older drivers to make anything work with an NVidia board.
The capacity of this hard drive IS low, but did you bother at all to look at the other specs?
10k RPM (almost all consumer drives are 7200 RPM) and NCQ support.
Did you know that the non-windowed Raptor X's predecessor was only 74 GB? Despite that it was an extremely popular drive for those that wanted high performance.
Maxtor's Atlas 15k II is 150GB and costs $710... Not much capacity, but it's basically the fastest hard drive on the planet.
While insufficient thermal paste is one issue, in such an old machine I'd first suspect heatsink dust clogging. (My 8200 has never had any overheating problems, although I have had to clean out the radiator/fans and re-lube the fans once.)
Almost all "mass media" reviews of products occur when the product is released.
As a result, unless there are blatantly obvious build quality problems - "feels flimsy" and such, build quality/reliability problems go unnoticed in the initial review. Many build quality and reliability problems are invisible until a product has been available long enough for failures to occur.
Examples: If you forget to save your position in a show when quitting out of it (e.g. to go out for the day), number pads make it easy to jump to a specific time.
Number pads also make it easier to navigate massive 200-channel EPGs.
Pretty much any new machine you buy nowadays will have enough CPU to decode 1080i in realtime. They might have problems with 1080p, but there isn't any content in that format available. I don't think the ATSC standards even allow it.
Aha. The impression I got from the previous poster was that the Logitech keyboards were missing important Apple-specific keys. It sounds like in your case, some remapping did need to be done and such remapping might cause a problem in OF.
I definately have used PC mice with Macs - the only difference is that until recently, Mac mice had fewer buttons.:)
Still, the guy I was replying to was bashing the Mac because of problems using hardware that wasn't designed for use with the Mac.
Oh, and another comment. Logitech doesn't make a single Mac keyboard. Since they ARE USB HID compliant, they will work with a Mac and are technically "Mac compatible", but since they weren't designed for a Mac they're going to be missing 2-3 Mac-specific keys without which your life is prone to be a nightmare.
Look at it this way - While there are many reasons that Windows sucks, would you laugh at a person who flamed it because it is heavily dependent on right-clicking for much functionality and they couldn't use such functionality because they have a "Windows-compatible" Apple one-button mouse? Yes, an Apple 1-button mouse WILL work under Windows since (like Logitech USB keyboards) it's USB HID compliant, but your life is going to be a miserable fucking nightmare if you use a one-button mouse with Windows. There are workarounds for not having the right button, but they are a royal pain in the ass.
BTW, before you complain about vendor lock-in, Apple has done NOTHING to prevent people from making third-party fully functional keyboards for their systems - look at Mac specialists like MacAlly and Kensington. (Kensington makes a lot of PC stuff now, but they were originally one of the main third-party Apple accessory manufacturers.) Just because Logitech doesn't bother to make a fully functional Mac keyboard doesn't mean that Apple has done anything to prevent them from doing so.
I believe the switching regulator is in the power supply, the "tips" just provide different voltage sensing resistors.
The way most switching power controller ICs work is that they continuously try to keep a voltage input equal to an internal reference voltage which is usually around 1.2 volts. To get higher voltages, a resistive voltage divider is used to sense the output voltage. For example, if one connected a 200k resistor between the output and the sense line, and a 100k resistor from the sense line to ground, then the output voltage would be 3.6 volts.
The nice thing about putting the divider network in the tip is that the power supply will now regulate the voltage that appears at the tip, AFTER any resistive losses between the switcher and the tip. (This works because the sense line going back to the switcher isn't carrying any current, only the output line.)
OK, between this and some of your earlier posts in the thread I've come to the conclusion that you're either a troll or completely clueless.
You do realize that the USB charging/sync cables available for many devices (cell phones, iPod, etc) do not require a PC to operate, and simply need +5V and ground to be provided to a standard USB female connector in order to work? As a result, you can have one cable that charges from a PC, or with a single "universal" adapter, from automotive power or AC. (An example is the BoxWave VersaCharger, which has a USB female connector and can either plug into a +12V DC auto power port or 120VAC home power, and charges anything that supports USB charging.)
Yes, 2.5W is too little for some devices, but it's sufficient for charging most portable electronics. I believe 1394 specifies even higher power per port. (12v @1A I think???)
You mentioned Mini-ITX in your article... Have you looked AT ALL into products designed to be used with Mini-ITX boards? There are numerous ATX compliant power supplies that operate using DC/DC conversion and only need a single 12V input, and most vendors that sell such DC/DC power supplies (such as mini-box.com) also sell high-wattage 12V supplies too.
Even ignoring whether or not the two patents in question which cover Least Cost Routing (LCR) techniques can be blown out of the water due to prior art... Google Talk doesn't do LCR in any form whatsoever! Google Talk only provides VoIP from one GTalk user to another for free (as far as I can tell at least...) I don't know how you can claim that a product does LCR for voice calls when it's only capable of making free calls.
Numb3rs season 1 - Maybe. I really liked it. So did a friend of mine who just started working on a Ph. D. in Mathematics. There were a few articles talking about the technical consultants they hired to make sure they got things Right, and it (for the most part) showed.
In season 2, it's become clear that the aforementioned consultants are no longer involved. In any case where they touch on electrical engineering concepts I feel competent to judge the show on, they botch it every time. I'm not qualified myself to judge how they're doing with the pure math, but the fact that my aforementioned friend went from loving the show to refusing to watch it because they got so many things wrong in the first two episodes of season 2 doesn't bode well for how they're doing with the technical accuracy in those areas.
While I can understand wanting to come up with a good story, it's inexcusable for them to be spreading misinformation where the truth would fit the story just as well. For example, at one point Charlie states that the GPS system uses satellites in geosynchronous orbit - HE'S WRONG! The main GPS constellation consists of satellites in highly elliptical orbits, and the main navigation system has no geosynchronous components. (The only geosync component of modern GPS are the satellites that broadcast WAAS correction data, and that is neither required for a navigation fix nor even run by the US military.)
Yeah, the (previously) great (despite the lame 1335speak name) CBS show about the mathemetician who helps the FBI solve crimes is what I'm talking about. Let me guess - you thought that GPS satellites are in geosynchronous orbit because you heard it on NUMB3RS? Well, guess what - the guy who they were consulting for technical accuracy in the first season clearly hasn't been involved in the second season. Among other things, there was a claim on the show that the GPS satellites are in geosync orbits, which is FALSE.
The actual GPS navigation satellites are in highly elliptical orbits. There is no way the system could work well if they used geosync satellites - Since all of the satellites would be above the equator, it would be difficult if not impossible to obtain good north/south positional accuracy. The only part of the GPS system (and it's arguably not even part of the NAVSTAR GPS system - it's an addon which the military has no involvement with at all) which are in geosync orbits are the satellites used by WAAS (EGNOS in Europe) to broadcast differential corrections data.
All your cable provider is doing when they increase your rate is increasing the cap they put on your modem itself. Thus, it's possible to get every last bit of your 6 Mbps even if there are a few other people sharing the system. That said, your system is almost surely oversubscribed somewhat, it's just that you're lucky that you aren't trying to use your full 6 Mbps at the same time everyone else is - otherwise that shared 30 Mbps would become overloaded.:)
Well, if you're right at the barrier of the capcity of a DVD disc, 54MB may matter.
That said, chances are that in such situations you're just going to be better off figuring a way to span multiple DVDs, especially given that while increasing compression might be enough for you today, chances are that you're going to exceed the capacity of that single DVD soon no matter what compression technique you'll use.
"if you download a file over gprs and each megabyte costs you 3$, then saving 200 megabytes means saving 600$, which is a price for a low-end pc or almost a laptop."
When you're talking about data files on the order of 2.5 GB, someone is going to find ANY solution other than GPRS. When you're talking about GPRS, even transatlantic sneakernet would be faster (and cheaper).
Plus many providers offer unlimited plans at higher monthly costs. (I know every US-based provider has unlimited data plans for under $100/month, and the U.S. is generally known for having significantly higher prices for mobile phone usage than anywhere else.)
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Flash memory has great read speeds and pays no seek penalties.
Flash memory has abysmal write speeds that are outstripped by any modern hard drive even under pretty heavy seeking.
It provides minimal advantages (mainly battery backup) over simply increasing system RAM. For 90% of people it makes more sense to increase system RAM.
Now if that drive used an older memory technology that was much cheaper per megabyte than modern system RAM, it would kick ass. Unfortunately, you need to load it with the same stuff you put into your system, and unless you need the battery backup, you'll get much more performance by simply sticking the memory into your system itself.
When accessing large files (not much seeking involved), modern hard drives have around double the sustained read/write speeds as that drive has CACHED read/write speeds. That thing's sustained write is only 1 MB/sec and its sustained read is only 2.3 MB/sec - even under incredibly heavy seeking, a decent SATA drive won't drop anywhere nearly that low.
That disadvantage of FAT causes excessive seeking on mechanical HDs.
It's not a problem with flash. Flash seeks instantly and the amount of data that actually needs to be written to the FAT is miniscule. I'd estimate less than 5% overhead at worst, most likely much less for large files.
Simply put, the raw write speeds of flash memory are LOW. Flash is slow as hell when you want to write to it. They've made huge advances in read speeds, but not write speeds.
Flash memory has slooooooooooooooow write speeds. Far slower than the hard drives' read speeds.
Battery-backed DRAM or SRAM would be a whole other story... Even slow DRAM that is a few generations behind current technology would provide an insane performance boost if used as a drive cache.
To avoid the nitpickers next time, you might want to say "solid-state nonvolatile memory is slow", since even though I'm sure you meant nonvolatile memory such as flash, everyone thought you were lumping in volatile memory (DRAM, SRAM).
:)
It's too bad drives based on volatile memory died out. There are always 1-2 models available, but they invariably use the latest and greatest memory, which is expensive.
It would be nice to be able to mix memory types in a system - Have 512M-1 gig of the highest quality superfast stuff, but then also have even more older and slower memory. (In essence, adding another level of caching). A system with 256M of PC3200 and 4 gigs of memory running at a speed equal to PC100 would most likely blow away a system with 1 gig of PC3200 in memory-intensive applications. (Yes, I know that right now, older memory is more expensive per megabyte than newer stuff due to economies of scale, but if the demand for older memory were much greater, there would be production of the older stuff at rock-bottom prices.) If flash memory can reach prices below $50/gig, older DRAM technologies should be able to achieve half that in volume.
As to flash memory - It's going to replace hard drives in some niches (it already has) where the storage required will likely not go up much from current requirements. (Automotive navigation systems for example - there's not much data you can add beyond what is already required. Compared to a good street database, POI databases are tiny and that's about all they can add.) It's never going to replace hard drives in most places HDs are used. Just like everything else in computing, new applications arise to take advantage of advances in technology (Examples - media servers where someone's entire DVD collection is stored on hard drives rather than DVDs for convenience of access.) See one of the first poster's comments about this guy clearly having no knowledge of BitTorrent.
Also, like you said, flash memory is slow. To those who mention the existence of 150X and higher SD media - Keep in mind those are absolute maximum ratings. Read speeds can easily go that high, but write speeds of almost all nonvolatile solid-state memory technologies are waaaay behind their read speeds (except for flash cards with very low read speeds - read speeds keep improving but write speeds haven't improved that much), or even the read/write speeds of hard drives. There is research being done into nonvolatile memory with high write speeds such as phase change memory devices, but those are still in labs and years away from the market.
99% of legit or semi-legit HD content isn't going to be in MPEG4 AVC. It's going to be MPEG-2 Main Profile @ High Level (MP@HL) obtained from:
An ATSC OTA HD tuner in the US
A DVB tuner in Europe
A QAM cable tuner for unencrypted US cable channels (There are more of these than you may think)
Firewire from a cable or satellite box
No one uses MPEG4 for HD content unless they are archiving stuff that was originally obtained as MPEG-2 at a lower bitrate. It is most definately not currently available from more than a tiny handful of legitimate sources, if any. Any modern machine is more than capable of decoding 1080i MPEG-2, which is why it's now nearly impossible to buy HD tuner cards that do hardware decoding nowadays (whereas around 2 years ago, there was one HD tuner card that relied on software decoding and at least 5-6 ATSC cards that did HW decoding.)
The part of a machine that gets upgraded/replaced most often these days is the video card, since new generations are released an average of every 6 months, and unlike with most other improvements in PC capabilities (especially CPU), the applications take advantage of the new features and capabilities almost immediately. (Many games nowadays are released with graphics quality options that will make the game unacceptably slow on any current hardware, in order to allow the game to "grow" with new graphics cards that make those quality options not kill performance. One example is Doom 3's highest texture quality, which required a 512M video card - almost none existed at Doom 3's release, and very few exist even now. A few years from now 512 will probably become the norm.)
:)
As a result, even if AMD changes socket types soon, it doesn't matter that much since the CPU is likely the last thing the OP will want to upgrade in the new system he buys. I don't think I've ever upgraded a CPU without getting a new motherboard, and I go MUCH longer between CPU upgrades than video card upgrades.
As to reccomendations - I think the original article poster is probably being paranoid about compatibility problems. As long as you stick with reputable motherboard and memory vendors, such problems are rare. I can only think of one such problem with one model of motherboard and a particular memory configuration, I don't even remember WHICH mobo that was though. (It was an older Athlon XP AGP board though.) Go to NewEgg, browse around, and read the customer reviews.
As to video card, I'd personally stick with NVidia rather than ATI. Even when ATI was well ahead of NV in performance, their drivers were so shoddy (especially in Linux, but their Windows drivers are horrifically inconsistent too) that buying ATI was like putting a V8 into a Yugo - wicked fast until you crash and burn. The one place I still hear compatibility horror stories is with ATI drivers - Game X works with ATI drivers older than version A, while Game Y requires drivers newer than version B which is higher than A. (Hasn't ATI ever heard of regression testing?) As a result I know multiple people who had to switch driver versions on a regular basis depending on which game they were playing. I've NEVER had to revert to older drivers to make anything work with an NVidia board.
The capacity of this hard drive IS low, but did you bother at all to look at the other specs?
10k RPM (almost all consumer drives are 7200 RPM) and NCQ support.
Did you know that the non-windowed Raptor X's predecessor was only 74 GB? Despite that it was an extremely popular drive for those that wanted high performance.
Maxtor's Atlas 15k II is 150GB and costs $710... Not much capacity, but it's basically the fastest hard drive on the planet.
The original i8k is an ancient model.
While insufficient thermal paste is one issue, in such an old machine I'd first suspect heatsink dust clogging. (My 8200 has never had any overheating problems, although I have had to clean out the radiator/fans and re-lube the fans once.)
Almost all "mass media" reviews of products occur when the product is released.
As a result, unless there are blatantly obvious build quality problems - "feels flimsy" and such, build quality/reliability problems go unnoticed in the initial review. Many build quality and reliability problems are invisible until a product has been available long enough for failures to occur.
Numbers can still be useful.
Examples:
If you forget to save your position in a show when quitting out of it (e.g. to go out for the day), number pads make it easy to jump to a specific time.
Number pads also make it easier to navigate massive 200-channel EPGs.
Pretty much any new machine you buy nowadays will have enough CPU to decode 1080i in realtime. They might have problems with 1080p, but there isn't any content in that format available. I don't think the ATSC standards even allow it.
Aha. The impression I got from the previous poster was that the Logitech keyboards were missing important Apple-specific keys. It sounds like in your case, some remapping did need to be done and such remapping might cause a problem in OF.
:)
I definately have used PC mice with Macs - the only difference is that until recently, Mac mice had fewer buttons.
Still, the guy I was replying to was bashing the Mac because of problems using hardware that wasn't designed for use with the Mac.
Oh, and another comment. Logitech doesn't make a single Mac keyboard. Since they ARE USB HID compliant, they will work with a Mac and are technically "Mac compatible", but since they weren't designed for a Mac they're going to be missing 2-3 Mac-specific keys without which your life is prone to be a nightmare.
Look at it this way - While there are many reasons that Windows sucks, would you laugh at a person who flamed it because it is heavily dependent on right-clicking for much functionality and they couldn't use such functionality because they have a "Windows-compatible" Apple one-button mouse? Yes, an Apple 1-button mouse WILL work under Windows since (like Logitech USB keyboards) it's USB HID compliant, but your life is going to be a miserable fucking nightmare if you use a one-button mouse with Windows. There are workarounds for not having the right button, but they are a royal pain in the ass.
BTW, before you complain about vendor lock-in, Apple has done NOTHING to prevent people from making third-party fully functional keyboards for their systems - look at Mac specialists like MacAlly and Kensington. (Kensington makes a lot of PC stuff now, but they were originally one of the main third-party Apple accessory manufacturers.) Just because Logitech doesn't bother to make a fully functional Mac keyboard doesn't mean that Apple has done anything to prevent them from doing so.
I believe the switching regulator is in the power supply, the "tips" just provide different voltage sensing resistors.
The way most switching power controller ICs work is that they continuously try to keep a voltage input equal to an internal reference voltage which is usually around 1.2 volts. To get higher voltages, a resistive voltage divider is used to sense the output voltage. For example, if one connected a 200k resistor between the output and the sense line, and a 100k resistor from the sense line to ground, then the output voltage would be 3.6 volts.
The nice thing about putting the divider network in the tip is that the power supply will now regulate the voltage that appears at the tip, AFTER any resistive losses between the switcher and the tip. (This works because the sense line going back to the switcher isn't carrying any current, only the output line.)
OK, between this and some of your earlier posts in the thread I've come to the conclusion that you're either a troll or completely clueless.
You do realize that the USB charging/sync cables available for many devices (cell phones, iPod, etc) do not require a PC to operate, and simply need +5V and ground to be provided to a standard USB female connector in order to work? As a result, you can have one cable that charges from a PC, or with a single "universal" adapter, from automotive power or AC. (An example is the BoxWave VersaCharger, which has a USB female connector and can either plug into a +12V DC auto power port or 120VAC home power, and charges anything that supports USB charging.)
Yes, 2.5W is too little for some devices, but it's sufficient for charging most portable electronics. I believe 1394 specifies even higher power per port. (12v @1A I think???)
Computer lacking a BIOS?
Take ten seconds (and I'm giving you way more time than any user with a clue should need) and think about what OpenFirmware is.
Yes, it's just another form of BIOS with a fancy name. (In fact, it happens to be more advanced than most typical PC BIOSes...)
You mentioned Mini-ITX in your article... Have you looked AT ALL into products designed to be used with Mini-ITX boards? There are numerous ATX compliant power supplies that operate using DC/DC conversion and only need a single 12V input, and most vendors that sell such DC/DC power supplies (such as mini-box.com) also sell high-wattage 12V supplies too.
Even ignoring whether or not the two patents in question which cover Least Cost Routing (LCR) techniques can be blown out of the water due to prior art... Google Talk doesn't do LCR in any form whatsoever! Google Talk only provides VoIP from one GTalk user to another for free (as far as I can tell at least...) I don't know how you can claim that a product does LCR for voice calls when it's only capable of making free calls.
Numb3rs season 1 - Maybe. I really liked it. So did a friend of mine who just started working on a Ph. D. in Mathematics. There were a few articles talking about the technical consultants they hired to make sure they got things Right, and it (for the most part) showed.
In season 2, it's become clear that the aforementioned consultants are no longer involved. In any case where they touch on electrical engineering concepts I feel competent to judge the show on, they botch it every time. I'm not qualified myself to judge how they're doing with the pure math, but the fact that my aforementioned friend went from loving the show to refusing to watch it because they got so many things wrong in the first two episodes of season 2 doesn't bode well for how they're doing with the technical accuracy in those areas.
While I can understand wanting to come up with a good story, it's inexcusable for them to be spreading misinformation where the truth would fit the story just as well. For example, at one point Charlie states that the GPS system uses satellites in geosynchronous orbit - HE'S WRONG! The main GPS constellation consists of satellites in highly elliptical orbits, and the main navigation system has no geosynchronous components. (The only geosync component of modern GPS are the satellites that broadcast WAAS correction data, and that is neither required for a navigation fix nor even run by the US military.)
Yeah, the (previously) great (despite the lame 1335speak name) CBS show about the mathemetician who helps the FBI solve crimes is what I'm talking about. Let me guess - you thought that GPS satellites are in geosynchronous orbit because you heard it on NUMB3RS? Well, guess what - the guy who they were consulting for technical accuracy in the first season clearly hasn't been involved in the second season. Among other things, there was a claim on the show that the GPS satellites are in geosync orbits, which is FALSE.
The actual GPS navigation satellites are in highly elliptical orbits. There is no way the system could work well if they used geosync satellites - Since all of the satellites would be above the equator, it would be difficult if not impossible to obtain good north/south positional accuracy. The only part of the GPS system (and it's arguably not even part of the NAVSTAR GPS system - it's an addon which the military has no involvement with at all) which are in geosync orbits are the satellites used by WAAS (EGNOS in Europe) to broadcast differential corrections data.
All your cable provider is doing when they increase your rate is increasing the cap they put on your modem itself. Thus, it's possible to get every last bit of your 6 Mbps even if there are a few other people sharing the system. That said, your system is almost surely oversubscribed somewhat, it's just that you're lucky that you aren't trying to use your full 6 Mbps at the same time everyone else is - otherwise that shared 30 Mbps would become overloaded. :)
Well, if you're right at the barrier of the capcity of a DVD disc, 54MB may matter.
That said, chances are that in such situations you're just going to be better off figuring a way to span multiple DVDs, especially given that while increasing compression might be enough for you today, chances are that you're going to exceed the capacity of that single DVD soon no matter what compression technique you'll use.
"if you download a file over gprs and each megabyte costs you 3$, then saving 200 megabytes means saving 600$, which is a price for a low-end pc or almost a laptop."
When you're talking about data files on the order of 2.5 GB, someone is going to find ANY solution other than GPRS. When you're talking about GPRS, even transatlantic sneakernet would be faster (and cheaper).
Plus many providers offer unlimited plans at higher monthly costs. (I know every US-based provider has unlimited data plans for under $100/month, and the U.S. is generally known for having significantly higher prices for mobile phone usage than anywhere else.)