@ Kyros

I agree with your perspectives, but regarding flexibility the Cell can perform the tasks accomplished by x86 CPUs with extra care.

The Cell can outperform even top current quad core x86 CPUs at double precision (although this yields suboptimal performance from the Cell, ideally developers should stick to half and single precision code formats, the Cell can crush the competition at this). For folding on the PS3 6 SPEs are being used.

Take a look at figure 6a (compare with quad-core Opteron and Clovertown processors, this document does not take into account the Cell's PPE):

http://www.cs.berkeley.edu/~samw/research/papers/ipdps08.pdf

Figure 5f is also interesting, using additional SPEs performance gains remain near linear with the Cell unlike the other processors.

GPUs will become more flexible though, some envision a merger between GPU and CPU tasks into one chip.

MikeB said: @ Kyros I agree with your perspectives, but regarding flexibility the Cell can perform the tasks accomplished by x86 CPUs with extra care. The Cell can outperform even top current x86 quad core CPUs at double precision (although this yields suboptimal performance from the Cell). For folding on the PS3 mainly 6 SPEs are being used. Take a look at figure 6a (compare with quad-core Opteron and Clovertown processors, this document does not take into account the Cell's PPE): http://www.cs.berkeley.edu/~samw/research/papers/ipdps08.pdf Figure 5f is also interesting, using additional SPEs performance gains remain near linear with the Cell unlike the other processors.

 

You keep repeating the same crap about that paper even though I disproved you last time you referenced it...

In that paper, they used TWO cell CPUs with 8 SPEs each. That's 16 SPEs vs PS3's usable 6.

They also conclude that each SPE provids 1 GFlop/s on double-precision arithmetic, which is very low. They even talk about "extremely weak double precision", section 5.5.

Now, I could realise all this after 5 minutes of skimming through the paper... I'll never understand why you, with your love for all things Cell, couldn't realize it.

 

PC always are better gaming machines. Just thing of it is that it cost way more to get a good computer to run some of the games. So that is why pc gaming in going downhile

What are we folding here? I could not be bothered reading the thread and that article. Lets make paper cranes like they do in Japan.

@ NJ5

Look at the figure more carefully, they both show results while using 1 Cell processor as well as using 2 Cell processors.

@ pimpcoop



No, back in the 80s and much of the 90s they sucked at games in comparison.

@MikeB: My point still stands, that's not a PS3 Cell, it has 8 SPEs instead of 6.

But as always, you cherry pick part of my replies and ignore the parts which prove you wrong. PS3's SPEs are simply not as good for double-precision calculations as other CPU cores are, and the paper states that quite clearly. It's still a fantastic processor for single-precision, but that's not what we were discussing.

 

GPU client/core update

We're pretty happy with the results of the QA from our new GPU core and we are working with ATI to do some more extensive QA.  If that goes well, the next step is a closed beta, and then an open beta (i.e. downloads on our web site).

It's taken a while to get to this point due to many fixes and changes under the hood.  Some of these changes have to do with new ATI development tools for using GPUs (these changes will help the reliability of the code as well as solve a lot of issues donor side, such as problems with drivers) as well as new science we've put into the GPU code, to bring it up to date with what we now do on the PS3 (in fact, some features of the GPU code are not present in the latest 1.3.1 PS3 version, but we hope they will be included in a future version).

http://folding.typepad.com/news/2008/02/gpu-clientcore/comments/page/2/

 

 

Basically they have the ATi GPUs doing what they have the PS3's doing so the comparison is now relevant.

 

Here is a recent chart showcasing the differnce between GPU's and the PS3.  Keep 2 things in mind.  1. The new ATi cards are not yet tested.  2. ONLY ATi cards are using the same code as the PS3.

 

 

This looks like RISC vs X86 all over again. Only in this case its Cell vs GPU and I think the latters got the better chance. Sure RISC/Cell were stronger at the start but mass market adoption made the differences irrelevent.

The Cell/PS3 use for Folding@HOME gained proliferation thanks to Sony touting it as a feature of the PS3. You don't get that same marketing push for PC's or GPU's.

@ Nj5

Again look at figure 5f, the cores show linear performance increase. You can easily determine how much double precision performance you get from 6 SPEs in this situation.

Of course the PS3 has 2 more active CPUs in addition to 6 SPEs, the PPE and one additional SPE used in the background by the CellOS.



The Cell's double precision performance is also remarkable, way more than you could achieve with the Xenon.

The Cell is good at double precision format calculations, but really shines supreme at half- and single precision.