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New 1 Kilowatt PSU - Too Much Power?
Steve from Hexus writes "While at the GC 2005 gaming convention in Leipzig, Germany, Hexus.net encountered a new 1kW PSU from Enermax, called the 'Galaxy'. At peak output it will use 1.4kW of mains power to provide a total of 66 amps across its various power rails. Who will actually have a need for this PSU, and when this amount of power is being consumed, shouldn't we be thinking about redundant power systems (or perhaps energy efficiency) instead?"
According to http://www.neoseeker.com/Articles/Hardware/Preview s/G70preview/11.html, an Nvidia 7800GTX draws 244 watts under full load. If you wanna go with SLI, you'll need at least 490 watts to power the video cards alone. And if you can afford that, you'll probably have plenty of other power-sapping toys and fans too.
550W will handle a dual core Athlon, dual 7800 GTXs, 4 SATA drives, 2 optical drives, and a decent number of case fans, at peak load.
I guess, since you specified Intel, you might need an additional 100W, but thats still just 2/3s what this thing outputs.
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Well, I haven't seen too many 650 watt PSUs, but remember the unit isn't going to pull more wattage than it's using, so a little overkill won't be environementally wasteful.
The price on the other hand...
"Oh my God. This is terrible. This is the end of my Presidency. I'm fucked."; ~ Donald J. Trump
Who said you were the target audience for this product? I am sure if you want to buy one enermax won't say, nah you're goofy for spending money on this everyone knows that a 250 watt compusa generic brand works for just as good
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Does it? I totally can not agree. I don't have anything resembling a gamer machine, just a simple asus a7v333 with amd 2800xp, pair of drives, a few cards, and ati 9600 video. That 250watt compusa generic powersupply does NOT cut the mustard. It looks like it works but I've established that most of my intermitent problems were a result of a lame power supply. My biostar motherboard (VIP) wouldn't even post with a generic 250watt compusa generic powersupply. Hell it rejected a 400watt PS.
250watts at 70% efficency, assuming that's even accurate is 175watts.
Below are generic numbers based on what I aproximate what my consumption is.
CPU--- about 70 watts [2ghz P-IV or high end AMD K7)
Video card about 40 watts [Geforce FX 5200 or ATI 9600)
Drives about 25 watts each [CD-rom spinup is typicaly about 30 watts]
PCI cards about 5 watts each
Memory about 10 watts each
Fans about 2 watts each.
Even with just one hard drive I'm so close to 175 watts it's not even funny. Two drives and Rom spin up.. I'm over 175watts without a doubt. While I'm sure the 250 watt generic compusa P/S might work in cases that have a modest video card, one drive, and modest power consuming CPU it's easy to see you might need more than that compusa 250watt PS.
This is not taking into account max power per voltage line, which the 3.3v in older power supplies might be limited to 14A (46.2watt).
http://www.jscustompcs.com/power_supply/Power_Sup
http://www.jscustompcs.com/power_supply/Power_Sup
Check for your self what you have and what PS is reccomended.
I agree 1KW is double or tripple what even a hard core gamer would need.... and is probally not money well spent, but neither is that 250watt compusa power supply. A fool and their money are soon parted.
There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
According to this, computers and peripherals used 21 billion kWh in 2001, out of a total of 1,140 billion kWh in the US. which means that residential computer use is 1.8% of the total. Probably gone up a bit since then, but I doubt to 10%.
If you include all electronics (including TVs and stereos, etc.) it reaches about 10%.
The cake is a pie
It's no where near as exciting as it sounds. Right now I have a regular 3-axis mill with a rotary table as a fourth axis. The steppers draw up to 3A per coil, making 24A total. My fifth axis would be a second rotary table mounted 90 degrees on the first. It would make really nice chamfers without changing tools.
PC Power & Cooling makes some of the best PSUs, hands down. For the machine you're talking about i'd probably run one of their 510 models that support SLI. Since you're friend has more money than he knows what to do with I might go with their 850 SSI psu. Its impressive to say the least. Overkill? Perhaps. Then again I wouldnt want to run a system that expensive with some shoddy PSU....besides the 850SSI is future-proof for at LEAST 2 years i'd say. Link to the 850SSI model here. http://www.pcpowercooling.com/products/viewproduct .php?show=T85SSI
actually, 400W will be enough for those, provide that the rating is true 400W
Do we need 1KW PSUs? no. I don't think so.
Generally, when I buy an overpowered PS, it's because I need a particular amp capacity on one of the rails. So I need a 550W PS for an Athlon 1.4Ghz box that probably draws 200W. This was because only the 550W model had the proper rating for +5DC.
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
Probably the same reason it won't have "overclocking features" - ie: there's not much overlap between the group of people who want $1500 Quad-CPU motherboards (that take $700ea CPUs) and those who want l33t SLI-video "gaming rigs".
Err, if it's a polynomial of degree 5, and there are 5 numbers listed that are supposed to be roots, then of course there are no nonreal roots -- the sum of the number of real roots and the number of nonreal roots equals the degree of the polynomial.
So REAL nerds recognized that you don't need to manually check it!
not as much as you might think.
HDD Power consumption
IDE/SATA drives only draw about 7-13W Idle/read&write, 15K SCSI drives a bit over 20W read&write.
Spin up might be a problem, but I'd assume you'd want to use cards that supported staggered sinpup on a setup that large.
So, yes 16 HDDs can pull quite a bit of power, about 300W for top end SCSI solutions. Though you wouldn't be thought of as particularly bright if you entrust a setup like that to a basic quality desktop PSU. And the quality of supplies you'd be using with a high end storage array like that (ie something in the N+1 redundant Zippy line) have been availible at well over 1000W for a while.
I think a 1000W PSU in a standard EAXT setup is massive overkill. I really have a hard time thinking of a workstation / stand alone server setup that would be too much for quality 500-600W PSUs to handle right now.
Anandtech reviewed a 4 CPU dual core Opteron setup from SUN while back, it only drew about 600W.
Just because a device is rated for a load does not mean it will use that load. Because you have a 200A pannel does that mean that you use 200A all the time? No, you doen't even come close unless your elecric range, water heater, hot tub, and resistive heat are all going at the same time. The real reason to have a 1000W power supply is to get clean and stable power if you use 200W. For our purposes a power supply has a part (rectifier) that chops off the negative voltage leaving you with a bunch of pulses of voltage. There is a second component (capacitor) that stores energy at the peaks and delivers it during the valleys. There is a third component (added to the rectifier makes it a bridge rectifier) that will turn the negitive voltage into positive voltage that fits nicely in the spaces inbetween the existing positive pulses. This doubles you efficiency by giving you twice the power at the output from the same input. Everything is great untill you put a load on the power supply, then you start to actually use the power out of the capacitor, this leads to a dip in the voltage called ripple. The higher the max wattage for a power supply the more power you can use before the ripple becomes a problem. Ripple in a processor is bad, this is why you will notice capacitors all over your motherboard and on some chip packages. These capacitors help smooth out the ripple.
If you run a 200W load on a 250W power supply then you will have a great deal of ripple. If you run a 200W load on a 1kW power supply then you will have much less ripple. ripple == fluctuating voltage == unstable pc
I have a Pentium D 8200, 2 GB of DDR2, Dual HDs (one SATA one IDE) and dual DVD burners, and a Radeon X800. Also, add a couple of firewire and USB devices. All of this runs off of a good 350W power supply with room to spare. If a 6800 (which uses more power than the 7800) uses about 135W, SLI would use 270W. That means you really only need a 500W supply. I think the idea above is right. By having an obsenely overkill flagship model, you not only make a couple of bucks off rich, poorly endowed kids who want a 1000W supply, but you get to brag that your company makes the most powerful power supply comercially available.
You might want to watch out actually. I've found stock that pc power supplies have way to much ac line ripple on the dc outputs. This is something you can see easily on any scope on even the very best pc power supplies.
While a power supply with a higher rating may have a cleaner output than a one with a lower rating, this is not necessarily the case. Without other measurements there simply isn't enough information to say.
Computer power supplies use a switching circuit to generate the output voltages. Not the simply, rectifier and filter system you described. They do use a recifier and filter, but this is only at the initial stage and ripple at that point doesn't significantly affect the output.
In a rectifier and filter supply, using a full wave rectifier does not double efficiency. It does allow you to get by with less filtering and a reduced peak input current.
Creating a full wave bridge rectifier doesn't involve adding 1 component to a half wave rectifier. In fact, you need 3 more components. A half wave rectifier is just a single diode. A full wave rectifier consists of 4 diodes.
Switching supplies do have ripple, and it is effected by the load on the supply. Some of the other factors affecting the amount of ripple are switching frequency, inductance of the switched coil, capacitance and resistance of the output capacitor, and input voltage.
Capacitors placed near ICs on the motherboard are for filtering out high frequency noise than can be induced on the circuit board traces. These capacitors are not normally the right values for filtering out 60 or 120 hz noise from a rectifier. If it weren't for induced noise on the traces, you could simply place one capacitor at (or in, as there already is) the power supply instead of one at each IC.
Your computer should run perfectly stable on any supply up to its rated output power and current. If a supply outputs so much noise that your computer is unstable before you reach the rated output, then it is almost certainly faulty or rated in such a way as to scam consumers.
With the same load, a higher rated supply might run cooler or with a cleaner output; but it depends on many different factors. You need to know things like output noise and efficiency. Output power alone is not enough information.
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All of whose base are belong to the what-now?
Look at the sticker on the side of the unit sometime..
I have, many times. Many just list a wattage, most of mine list Max wattage and peek output. For example this crappy supply that came with my full tower is listed as 300watt but clearly marked peek output total 165watt. To me that says 55% efficent. Utter crap but never the less any time I actually see it clearly marked max output the value is lower than the wattage rating by there and abouts of 70%, in rare cases less, in even more rare cases more.
When it's not clearly printed on the label if the wattage listed is input or output, I assume input. If i'm wrong i'm wrong, but it's been my experence that's the standard.
Well, to be fair, it does for absolutely everyone who isn't using a Pentium 4. My hottest 2GHz+ system is only using 100W when maxed-out, the rest are even lower.
I was almost happy with the cheepo compusa PS, it worked MOST of the time. I would crash once a day though. But I swapped it out with something new and i'm stable as a rock. Works just great on my other machine that's an AMD 1700 with only one HD.
That is clearly a case of defective products. Either the motherboard is on it's last leg, or
those dirt-cheap power supplies you are getting are utter crap.
Well the motherboard was pretty damned new, and it's still in service under a different power supply. The PS was what came with the full tower... so I would agree the PS was utter crap. In fact there is no shortage of utter crap powersupplies on the market.
I would very much like to know how you "established" that. Even if you're right, it's almost certainly a defective unit, not a case of your system exceeding the rated capacity.
Basic trouble shooting. Had odd ball problems a while after swapping out that 400watt unit that the Biostar motherboard rejected. Matter of fact, I have a stack of power supplies here many are pulls from HP systems (Vectra VE series)... I would crash under the following conditions....
1. After the system had been on for a while... I would put in a CD and crash
2. I would play a game... after about 1/2 hour crash
3. Microsoft word.. 15min or so after using it.
I however would not crash under the following condtions
1. disconnecting all my HDs except for one
2. Using the crap power supplies but powering my drives with an old at power supply, but the motherboard with an ATX power supply rated anywhere from 150watts (e machine pull) to 400 watts.
3. Swapping out the power supply with a new one, one I guessed was not utter crap
The most stable supplies i have with the exception of this new one are pulls from HP vectras by Delta Electronics.
There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
"Mains power" is English for what Americans call "outlet power".
Example usage "You can run this radio from a battery, or you can plug it into the mains".
No, that, folks, is the fundamental theorem of algebra.
nothing new... 30 or so years ago good PDP11 used two similar (in terms of output power) units for a total of 2kW (some setups probably needed even more) http://www.psych.usyd.edu.au/pdp-11/psu.html
not to mention systems built of vacuum lamps from the ENIAC era - they needed their own power stations...
All power supplies have a "sweet spot" from an efficiency standpoint which is normally 75% of rated power. That would imply that this power supply is most efficient around 750kW. At 350kWs I would guess this supply is only 65-75% efficent. Perhaps it is designed to be efficient across a broad range of output.
http://en.wikipedia.org/wiki/Flux_capacitor
And don't forget, "it's The Hacker to you!"
Just to piss off the mods,
ACHTUNG! Das computermachine ist nicht fuer gefingerpoken und mittengrabben. Ist nicht fuer gewerken bei das dumpkopfen.
A kilowatt is a bit light-weight for a toaster
Maybe for a four slice toaster. But for a two-slice model a kilowatt would probably be just right or even a little bit of overkill.
My two slice toaster uses 800 watts according to my kill-a-watt. If I put it on "bagel" mode (turns off one side of the heating elements in each slot) it only uses 600 watts.
In any case you wouldn't use a PSU for a toaster anyway. The highest voltage you can usually get out of them is 12VDC. At that voltage you'd need 66 amps to deliver the 800 watts my toaster uses. 66 amps would require a pretty thick piece of cabling. Of course since it takes in 1.4KW to provide 1KW of actual power you could probably slowly toast your bread off the waste heat that this thing will generate...
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
There appears to be a number of homebrew designs here. One other thing that I noticed from my hour of looking at the subject yesterday is that you need a dedicated computer to control the system. There appears to be Penguin CNC, which seems to do the job, using Realtime Linux.
Jumpstart the tartan drive.
=) Good joke.
But having a BS-CE, and having done a senior project involving USB back in school, I can't just let the inaccuracy of that statement slide...
<pedantry>
The power capacity or amperage of the power supply will have no effect on an individual port-powered USB device. The USB standard divides devices into two power classes: low-power (less than 0.25A) and high-power (between 0.25A and 0.5A). And IIRC, one powered USB port can only source a maximum of 1A to all devices connected through that port at any given time. If you need more, you've got to use a self-powered hub.
</pedantry>
I recently bought a manual Bridgeport milling machine, and am in the process of converting it to CNC.
I will be using Linux EMC to control it. This is a program which uses Linux + either RTAI or RTLinux for realtime. It does 6-axis control, and has pluggable kinematics modules (ie, it can control X-Y-Z milling machines, Stewart platforms (hexapods), radial arm robots (like the PUMA 560), etc).
The G-code interpreter is actually the reference RS274NGC interpreter, originally developed at NIST. There is still some NIST involvement inthe project, but it's mostly community-driven now.
I am also using an FPGA-based step pulse generator made by Pico Systems, and excellent servo drives made by GeckoDrive. (no links to prevent slashdotting) The external step generator isn't necessary, I'm just using it because the step rate I can get from a PC parallel port isn't high enough for my machine. The resolution of my machine is 40000 steps/inch, or 0.000025" per step, and the PC can only generate around 25k-50k pulses per second. Since I want faster rapids than 60 IPM, and I don't want to sacrifice resolution, I Need the faster pulse generation of the external board.
As for cost, EMC is free. Servos are expensive as hell from normal sources, but there are plenty on eBay for $125 - $150 each. The servo drives are $110 each, and the interface board (which also has lots of digital I/O) is $250. Add in an old slow PC (Pentium 333, for example) for $10, and you can do the whole motion control thing in the $1000 range, plus the actual machine.
- The Sigless Wonder