5 replies to this topic

[poser]

Hi... the last time I bought a computer, I was told to get an Intel because it's a lot faster. Someone with a almost an equivalent Intel processor got wildly better fastPI results. I bought one and was disappointed how at least in Boinc, while I got a bit better benchmark results, that didn't translate into significantly faster crunching. So now I'm thinking it's foolish to buy Intel. If you disagree for a reason, I'd like to hear it out.

So I'm looking at MSI K9A2 plat which I understand could actually fit 4 of those double-width cards. But I'm unsure, what kind of cooling and PSU's these would require. I've read that it is possible to use 2 PSU's, a bigger for the main PSU and smaller for the GPU's. I have no idea what the power requirements would be...anyone know? If 4 would require water cooling, would 3 do without?

I hope I wouldn't have to go into water cooling. I'm not sure if I'll be using a case. At least the other PSU has to stay outside...

Also since Newegg prices for these are as low as they are, I'd need someone to forward them to me to the old continent. I think that besides chungenhung someone else mentioned being available for this kind of task...? I'm thinking that with 4 cards this big, it's very hard to avoid customs so better report the real value on the sticker.

edit: Just read that someone, in October, got 5800 PPD out of 9800 GX2. I thought that it had 128 stream processors and was not supposed to take any hit with the new WU's. If 9600 GSO scores 3600 PPD, it would seem that only an idiot would buy 9800 GX2's?! What gives...?

Edited by poser, 12 January 2009 - 09:26 AM.

[poser]

Ok, got a rensponse from the person who cited that PPD for the 9800 GX2. Things aren't that bad it turns out

That ~5,800 PpD was per GPU Core with the fast protiens and the fastest FahCore.
The four GX2's where doing ~47k PpD.
Now with the slower protiens and FahCores, each GPU core is doing ~5,200 PpD.
The four GX2's now give me ~42k PpD.
The slowest I've seen it fold with the 511 pointers was ~3,200 PpDpCore or ~33k PpD for the box.

[kismet]

So now I'm thinking it's foolish to buy Intel. If you disagree for a reason, I'd like to hear it out.

Well, they are faster than the competition (overall and in folding too as far as I know), is that enough of a reason?
What did you compare to and what where you disappointed with? Which CPU from Intel did you buy? Did you go from a dual to a quad? Does the software scale?

Obviously if you go for the GPU folding the CPU won't matter as long as it can handle the cards. Someone experienced with multi GPU folding systems should chime in...

Edited by kismet, 12 January 2009 - 08:28 PM.

[chungenhung]

a low end dual core CPU can easily feed a 4 GPU monster.
The CPU usage while using 4 nVidia GPUs is less than 5%.
So, CPU does not really affect GPU folding speed if at all.
However, Intel CPU does outperform AMD in WCG or F@H using CPUs.

[poser]

Well, they are faster than the competition (overall and in folding too as far as I know), is that enough of a reason?
What did you compare to and what where you disappointed with? Which CPU from Intel did you buy? Did you go from a dual to a quad? Does the software scale?

I'm pretty sure the processors were Sempron 3800+ and C2D E4400. That gives Sempron 0.2 ghz headway, however, I overclocked them and although I don't remember the exact numbers, Sempron overclocked more (%-wise) and I remember being disappointed as E4400 and that 'range' of processors was claimed to be highly overclockable.

I don't know what it means that the software scales. Boinc (or Rosetta to be more exact) can use 100% of the CPU.

Obviously if you go for the GPU folding the CPU won't matter as long as it can handle the cards. Someone experienced with multi GPU folding systems should chime in...

No, it means to me. I do Rosetta as well.

Edited by poser, 14 January 2009 - 01:38 PM.

[sentinel]

a low end dual core CPU can easily feed a 4 GPU monster.
The CPU usage while using 4 nVidia GPUs is less than 5%.
So, CPU does not really affect GPU folding speed if at all.
However, Intel CPU does outperform AMD in WCG or F@H using CPUs.

I get the logic but when I run a standard CPU client on one of my low end dual core boxes housing a GPU it instantly lowers the PPD on FahMon.