My XBox 360 vs PS3 comparison (mostly technical)

[sieanr]

Final-Fan said:

The main part I take issue with is this; The clock speeds he cites and overlooking the disadvantages to XDR (namely very high latency). Not to mention the completly out of whack implication that the 360 design is like a cheap mobo.

I thought (and Wikipedia and others agree) that it was RDRAM that had latency issues, and that XDR had solved that problem.

One of the arguments that pops up with RAM in the respective consoles is that the RSX can be just as flexible with its RAM usage as the 360, ie use all 512mb.

While the RSX can acess the XDRAM, but at a significant latency penalty. Since the crux of his argument was that the split RAM desing was superior to the 360 pooled design, I think this is a somewhat major oversight - especially given how large textures this gen are.

Another thing he overlooked was the hardware tesselator in the 360s GPU. One of the things brought up here was the supposed lack of bandwidth between the CPU and GPU in the 360s design. However, the hardware tesselator can take a lower poly model and tesselate it into a higher poly model, which saves heaps of vertex data shuffling from the CPU to the GPU. This is also relavent because you hear PS3 devs talk about using the SPUs to do geometry, yet the tesselator can do many of these things, in hardware on the Xenos.

@oli2, you win the internets. The SPUs are much more like shaders in a GPU than a seperate core. They can access memory independantly, but they must recieve all their tasks from the PPE. THe PPE could, in theory, be swamped with other work and significantly impact the performance of the SPUs. Not to mention the Cell can only run two threads.