360 CPU and Cell are fairly equal according to Dave Shippy

[heruamon]

joeorc said:

Procrastinato said:

^^ The Cell's SPEs can perform many functions similar to GPUs, but they aren't GPUs. Anyone who has ever written a software rendering engine would concur that the SPEs downright phenominal, and supremely flexible, for such an endeavor -- but they aren't going to replace a dedicated GPU when it comes right down it it. They can assist the RSX by relieving it of some work, realistically. "Preprocessing" some graphics tasks, if you will.

That being said, in terms of real-world performance, the Cell is a little more powerful than the Xenon, but the 360's GPU usually typically makes up for the difference, unless the engine is a dedicated PS3 one, because not many games are CPU-bound, they are GPU-bound.

I think the issue most people fail to understand, regarding the Cell, is that the Cell itself is not some magical phenominon that is going to change the landscape of computation -- the idea* behind the Cell is, however. Future iterations of the same concept will outperform "full" multicore architectures, from a heat perspective, from a transitor count/cost perspective, and every other perspective that matters, except a software development perspective.

And that last bit is where architecture's like the Xenon get their praise from.  In the hurried modern world, where time and budget is always in a concern, the Xenon has a fair sized advantage, and that's not to be underestimated.

 

* The idea is that "convenience" features of a processor, like a huge cache, out-of-order execution, and a good branch predictor, are much more expensive, and much less worthwhile, than the extra basic cores you could put on a chip are, with the same transitor count.  More power, less heat, less raw materials.  The added performance comes at a cost to the software developer, who can no longer rely on the aforementioned crutches to allow his/her code to pass for "fast".

while i pretty much agree with what you stated..the Cell processor is indeed a CPU/GPU combo chip.

and yea it is not meant to replace a dedicated GPU for the most part. except now the smaller nm scale CPU/GPU combo chip's do provide the didicated GPU finction in Mobile devices, that would require such low power processor's with the graphic's use ability to replace dedicated GPU's that would otherwise offset the advantages of the CPU/GPU chip's provide like you stated in power /watt and transister count.

but here is DR. Hofstee has stated this here is the PDF

lanl.gov/orgs/hpc/roadrunner/rrinfo/RR%20webPDFs/Cell_Hofstee_Non_Conf.pdf

and how AMD and Intel and Ati are also heading in that same direction.

 

The shift of AMD and Intel is driven by profits, and not necessarily capability.  Don’t get me wrong, as I’m not saying it’s totally impossible to deliver on this capability, but in a lot of respects, this reminds me of M$ attempts to organically put more function into windows…it extremely complicates the solution, and leaves more room for loss of efficiency.   AMD is doing so, because they own ATI, and are looking to deliver a cheaper solution to compete and stay alive, but Intel is shifting in this direction to rebuff the comments from Nvidia about the importance of the CPU in the mix.  Overall, I don’t think its going to work, and I think at the end of the day, CPU/GPU will remain separate…another example is the Sound Card…you notice the difference when you have a dedicated soundcard, vice using the board sound. 

BTW, That pdf had an interesting comment that somewhat outlines the expectation some had for Cell and the PS3...

“Innovative Chip is best high-performance embedded processor of 2005

We chose the Cell BE as the best high-performance embedded processor of 2005 because of its innovative design and future potential....Even if the Cell BE accumulates no more design wins, the PlayStation 3 could drive sales to nearly 100 million units over the likely five-year lifespan of the console. That would make the Cell BE one of the most successful microprocessors in history.”

 

As far as I know, no other major system uses the Cell/Broadband Engine processor, although some are “planning” to use it, which means the ps3 had better start selling A LOT of console in the next year.  My gut tells me that Intel is going to make a very strong to M$ to get its chips in the next console, which would present some interesting dynamics on cost.