Are there any CPUs that come close to the power of a GPU?

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JoshSilver
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Are there any CPUs that come close to the power of a GPU?

Post by JoshSilver »

When building my rig, my original idea was 1 thread per GPU. I wonder though if getting a really good CPU might make any kind of significant progress on WUs?
JimboPalmer
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Re: Are there any CPUs that come close to the power of a GPU

Post by JimboPalmer »

Josh, for the last 50 years, the 'good stuff' was just around the corner.

Currently the 64 core/128 thread AMD EPYC processor is the 'real soon now' CPU.

If I had to buy now, I would get a current EPYC, but the next one seems very powerful. (If you are made of money, buy the slowest EPYC now and upgrade before the year is out)

https://www.tomshardware.com/news/amd-e ... 38939.html

https://wccftech.com/amd-epyc-rome-zen- ... es-report/
Last edited by JimboPalmer on Wed Apr 24, 2019 9:42 am, edited 1 time in total.
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foldy
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Re: Are there any CPUs that come close to the power of a GPU

Post by foldy »

It depends if you have a slow GPU then a many core CPU can compete. But if you have a fast GPU or many slow GPUs then CPU cannot compete.
CPU 8 core ~= 100k PPD

And the 32+ core CPUs are for servers which means they run at low clock speed 2 Ghz and low voltage to save power and heat. So instead of 4 Ghz CPUs these server CPUs only get half the speed per core.

Epyc 64 core ~= 400k PPD
Russ_64
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Re: Are there any CPUs that come close to the power of a GPU

Post by Russ_64 »

The short answer is No, not even close.

A fast, powerful modern GPU (Geforce RTX or top end GTX) will do ~1.5 million PPD versus top end desktop CPU at ~100k.

If you are a gamer, then buy the best GPU you can afford and a decent 4 or 8 core CPU (one will be used for FAH on GPU) and rest can run FAH if you choose. When you game you will be happy and the rest of the time it can Fold (while you surf and do general PC stuff).
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bruce
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Re: Are there any CPUs that come close to the power of a GPU

Post by bruce »

If you are going to spend money explicitly for FAH, the simplest comparison is GFLOPS/$. That's not a perfect basis for comparison, but it comes pretty close. You'll have to add the initial hardware cost to domr factor for your cost of electricity over the life of the hardware to get a rational number for what I've called "$"

Of course if you're a gamer, then you also have to evaluate something equivalent to FPS/$.
MeeLee
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Re: Are there any CPUs that come close to the power of a GPU

Post by MeeLee »

Yeah, most desktop CPUs, or older Server CPUs get about 30KPPD, which is the same as a budget GPU (GT 1030).
Modern gaming CPUs with 6 cores or more, running at 4 to 5Ghz, might get 100K PPD, but they cost a lot of money, draw a lot of power, and are only comparable to a budget GPU like the GTX 1050.
It makes more sense to not upgrade a CPU, but buy one of the newest generation GPUs, like a GTX 1660, GTX 1660ti, or an RTX card.
You'll end up spending less than buying a powerful CPU in initial purchase as well as your running cost (electricity, which for folding 24/7 does add up).
Theodore
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Re: Are there any CPUs that come close to the power of a GPU

Post by Theodore »

foldy wrote:It depends if you have a slow GPU then a many core CPU can compete. But if you have a fast GPU or many slow GPUs then CPU cannot compete.
CPU 8 core ~= 100k PPD

And the 32+ core CPUs are for servers which means they run at low clock speed 2 Ghz and low voltage to save power and heat. So instead of 4 Ghz CPUs these server CPUs only get half the speed per core.

Epyc 64 core ~= 400k PPD
Lol!
Just look at their cost, not to mention the additional hardware cost, like motherboards!
What they do have going for them, is if you want to run more than 6 graphics cards for folding, at which you probably will need to run a 2 phase, 220V line.
bruce
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Re: Are there any CPUs that come close to the power of a GPU

Post by bruce »

I find that computers which have completed a 3 year lease and have been "refurbished" by reputable recycle firms make a reasonable choice. They are much cheaper than a new gaming machine but they have reasonable CPUs (several years old) and they make a good platform for a single GPU that is also on the high end of mid-range. (You'll probably be limited to the Low Profile choices.)

Connect several of them to a KVM switch.
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