Treblaine said:
With that I can say with confidence, CPU is not such a limit on frame-rate, in fact Carmack explicitly stated that it was the rasteriser (i.e. GPU, he uses the older term because he has been in the business for so long) that was the problem, which is completely separate from The Cell. In fact everyone has been incredibly sidetracked by the hype around The Cell since graphics are mainly rendered in a GPU, not CPU. The entire reason GPUs invented was because CPUs are so inefficient at rendering multi-polygon and large textures i.e. what makes games today look good. Some effects can be effectively offloaded to a CPU but they are still inefficient and need very careful resource management = hard to program.
But you forget, the cell is designed to actually offload some of the processing from the GPU on to the Cell. Thats the way they designed it.
Go play Uncharted, or MGS4, All those cutscenes, Are rendered in REAL TIME. They are able to DO that by putting the processes between the CPU and the GPU. The SPE's are incredibly powerful, They are fast, really really fast. And there are six of them.
The CPU isn't inefficient at rendering multi-polygons, its inefficient because its running the OS, running everything involved with the game, all the physics, particles, AI, ect. Its doing a LOT of stuff at the same time. All the GPU is, is a 2nd Proccessor dedicated to graphics. If you put a 2nd CPU in your pc and dedicated it to graphics it would virtually do the same thing. Nvidia Is, I believe, making there own GPU/CPU that will supposedly replace Intel/AMD.
Also, I know enough about the PS3 to know the PS3 only has FOUR Synergistic Processing Units' (SPU) available rather than 6 as was originally touted. This is because Teh Cells used in PS3s are basically all units that fail Sony's quality control for other commercial use (mainly supercomputers, servers, etc), where one of the 6 cores is faulty so is disabled so only 5 physical cores are active. On top of that the 5th core is ALWAYS reserved for PS3's background operating system, that 5th core is not available to developers now and no sign of it ever being made available in the future.
Actually you got that wrong, the SPU's also called SPE's, and about a dozen other things, there are EIGHT in the Cell, 2 of the SPUs are locked. 1 is locked for the Core System (Aka it runs the OS), the other is locked because it is faulty. Its a cost saving measure. They have 8, 7 are good, 1 is defaulty, what are they going to do with the shitty one? They have to have ONE for the OS, and they can't apparently give devs an 'odd number' of SPU's.
The SPUs are so complex the main Power Processing Element (PPE, actually almost identical to one of the three cores in Xbox 360's Xenon processor, only at a lower clock rate) is almost totally devoted just to managing the 4 + 1 SPUs.
Its main processor I believe is a 2.4ghz Single Core Processor. It might be 3.0, (was 360 3.2?) It isn't devoted to the SPU's, but thats part of its job. THIS IS WHY people who made ports 2 years ago, sucked. THEY PUT EVERYTHING ON THE SINGLE PROCESSOR!
So it is a lot more like 3 vs 4 in terms of sheer CPU power of 360 vs PS3 but bottlenecks like the rasteriser that Carmack has mentioned is a bit like having a 1000 horse power engine in a car yet spindly bicycle tires; if you can't transfer the power to the road then you aren't going to get the speed you expect.
Again, you fail at reading its still 3 vs 8. 7 SPU's, and one main central processor.
Also, Your last analogy fails.
Never heard of the Tweel?
http://www.gizmag.com/go/3603/
/fail!