PS3 vs quad core PC

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Postby toTOW » Thu Dec 06, 2007 2:52 pm

I'll be able to tell more precisely when the HD3870 will fold :mrgreen:
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Postby toTOW » Thu Dec 06, 2007 7:02 pm

Cprossu wrote:
PS3 are drawing 170-200W depending on the version you have ...

Q6600@3.2 GHz is taking only 130W ... it raises at 180W is you add the load of my HD3870 (which can't fold yet).


hmmm

according to my watts-up, this X2 3800+ rig with a mildly overclocked X1900xtx is pulling 175 watts from the plug while folding on the gpu...


Does it takes the cos(phi) into account for its measure, or does it only displays U * I :roll:
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Postby 7im » Thu Dec 06, 2007 7:18 pm

toTOW wrote:Does it takes the cos(phi) into account for its measure, or does it only displays U * I :roll:


What does the power factor have to do with measuring the watts used at the outlet? Most of today's PC power supplies have high or active PF correction to reduce loses to almost nothing.
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Postby toTOW » Thu Dec 06, 2007 7:26 pm

PSUs are not resistive charges ... so the P = U * I formula is not valid (it give the apparent power in AC configuration, in VA). If you want the real power, in W, the formula is P = U * I * cos(phi).
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Postby 7im » Thu Dec 06, 2007 7:46 pm

Okay. Go ahead and use the correct forumula and calculate this out. How many decimal places of difference is there in the answer?
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Postby toTOW » Thu Dec 06, 2007 9:14 pm

Well if you have a value of 600VA (for an UPS for example), it makes 480W of real power. A typical (mean) value for cos(phi) is 0.8.

Here is a nice article to discover the basis of AC power : http://en.wikipedia.org/wiki/AC_power
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Postby 7im » Thu Dec 06, 2007 9:48 pm

Again, we are not talking about a UPS. We are talking about the example posted above where a computer is drawing a specific amount of watts from the wall to run the fah client.

Please do the math with that example, where as I already stated, most of today's ATX power supplies have a PF of 95% or above, or Active PF at 99%.

I like this wikipedia entry myself: http://en.wikipedia.org/wiki/Power_fact ... Active_PFC
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Postby toTOW » Thu Dec 06, 2007 11:54 pm

So if we consider that the active pfc gives us a cos(phi) ~ 1, so that VA are almost equal to W here are the new number for my Quad :

Quad folding : 210W
Quad folding + GPU load (from GPUQuant application) : 300W (GPU in 2D mode)

It's still reasonable for the number of points produced :mrgreen:

edit : I forgot to tell that these numbers include the power of a LCD 19".
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Postby etchells » Fri Dec 07, 2007 1:57 am

alancabler- you are just what I was looking for- perfect- thanks for the technically founded information which I will turn into advice- so what I take from your input is this: I am going to buy another PS3 because they crank- I will do this right away. But, what you seem to indicate is the ATI gpu's crank for folding as well, I am currently running Nvidia cards in SLI in my main PC- so if I understand you right if I replace my cards with ATI cards I can generate more results for folding?? It's personal to me, a family member of mine has one of the conditions folding is researching and there's nothing I can do, but I can build or buy machines that will help folding, I can buy another PS3 and I can surely replace my video cards- honestly I've never studied ATI cards, which model is the best for folding?? My heartfelt thanks for your reply and your knowledge and your advice. DTG

another thought. what is the linkage of the ATI GPU's to the CPU performance, more, can I build cheap machines from a CPU perspective and populate them with the correct ATI GPU's or is there a coupling between the CPU and GPU for optimal processing for folding??
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more on the best folding solutions

Postby etchells » Fri Dec 07, 2007 2:15 am

ac- here's another set of ideas- given a fixed budget- given gpu's cost 200 to 300ish, given a PS3 costs 399- my, unfounded on fact, feel is that buying PS3's to run as folding machines is probably the cheapest alternative as well as probably at least hightly productive for folding; given you seem to be part of the inside team for folding with regards to knowledge, what is the relation of the productivity of a PS3 vs a GPU with the latest ATI GPU? sorry for pounding you with questions but, you seem to be a person who is in the know and can help me through my situation. My best regads- DTG
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Postby bruce » Fri Dec 07, 2007 2:36 am

etchells wrote:another thought. what is the linkage of the ATI GPU's to the CPU performance, more, can I build cheap machines from a CPU perspective and populate them with the correct ATI GPU's or is there a coupling between the CPU and GPU for optimal processing for folding??


There is virtually NO relationship between the CPU speed and the throughput of the GPU. You need a motherboard that supports the GPU (i.e.- a Pentium II probably won't work in a MB with a PCI-E slot) but as long as you dedicate a CPU to managing the GPU, you'll can use almost any CPU. You only run into trouble if you try to run a second FAH client on the same CPU-Core.
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Re: more on the best folding solutions

Postby bruce » Fri Dec 07, 2007 2:41 am

etchells wrote:what is the relation of the productivity of a PS3 vs a GPU with the latest ATI GPU?


The GPU client does not yet run with the latest GPUs. There have been hints that a new GPU client might be available for those newer GPUs but nobody can do anything except guess when that might be or how fast it's going to be.

We all hope it is soon, and that it's very productive, but we won't know until it actually happens.
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ok guys

Postby etchells » Fri Dec 07, 2007 2:48 am

so there you go, in the near term the answer seem to be for me to buy as many PS3's as I can afford and run them as folding machines. If at some point as PC or PC with a better DAMMIT GPU would be a better investment then I can go that way, honestly the form factor of the PS3 is better for me and it eliminates the problem of an operating system etc etc, so until something more compelling comes along I guess I will end up buying as many PS3's as I can afford for my folding efforts.
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Re: more on the best folding solutions

Postby alancabler » Fri Dec 07, 2007 3:56 pm

etchells wrote:ac- here's another set of ideas- given a fixed budget- given gpu's cost 200 to 300ish, given a PS3 costs 399- my, unfounded on fact, feel is that buying PS3's to run as folding machines is probably the cheapest alternative as well as probably at least hightly productive for folding; given you seem to be part of the inside team for folding with regards to knowledge, what is the relation of the productivity of a PS3 vs a GPU with the latest ATI GPU? sorry for pounding you with questions but, you seem to be a person who is in the know and can help me through my situation. My best regads- DTG
1st, I made a BIG mistake in my earlier post by grossly understating the power of a q6600.

Interpolated info derived from fahinfo.org and other sources:
a stock 2.4GHz Q6600 folds @rate 30-50 GFLOPS,
depending on the WU, so quad rigs rival PS3s and GPUs in power, and especially OC'd Qs. Quad- core CPUs are also (for now) much more versatile than other platforms, and the current points system reflects that fact. Professor Pande has announced upcoming changes for the points system, however, so who knows...
Quad machines are expensive to build- even stripped, they can cost >$500 with a really good (OC'ing) motherboard.

The absolute cheapest method for adding a lot of power to the project is to add a GPU to an existing machine. Older AGP rigs really benefit as an AGP X1950GT will produce 500ppd @ stock speed- adding ~ 65 GFLOPS to the project. Those cards are <$150.
The fastest GPU (until new GPU client)) is the X1950XTX on PCI-x16 bus. They are known to produce >90 GFLOPS.
All thoughts of adding a GPU should probably be put on hold, due to upcoming changes which may allow use of the powerful ATI 3800 series (which will also be available in AGP flavors). An official update will probably be made "soon".

note: Not sure which client(s) you are running on your AMD dual-core, but if you aren't running SMP, you could easily add a PCI-x GPU (they're cheaper than AGP) and run 1 instance of normal CPU folding + 1 GPU instance. Don't do it if your machine is running SMP, however.

PS3s are great and fold @rate >50 GFLOPS. They're also simple and fuss- free to use, and you can't go wrong by adding all the PS3s you can buy.

Ps Thanks for the kind words, but I'm just some guy out here "folding", and have no access to special info- I'm just long- winded, and sometimes have an actual clue...
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great reply alancabler

Postby etchells » Sat Dec 08, 2007 12:53 am

alancabler- thanks much for the additional info. I am running the SMP client on my AMD X2, deleted it and was going to go with one instance of the 5.x client and a GPU as well but, it seems the folding guys don't run a GPU client for NVIDIA cards and I'm running SLI with 2x7900GT's. So I will probably go back to the SMP client and hopefully my AMD cores will be helpful to the folding guys. I am sorry for all my questions, I am only into this folding thing for a few days and trying to get smart fast but, I seem to be churning some; sounds like what I should do is wait for the new ATI card and replace my NVIDIA cards, I'll have to do some research and see when the new DAAMIT cards are out then then it will be a decision as to if the cost of the card is worth it compated to more PS3's; any idea when the new folding GPU client is out? also, how do you get smart on the folding info, is it here from the forum and if so which particular piece of it or do you have to read it all to stay up on things? Much thanks for your help!
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