How Important are FLOPS to Gaming Performance?

[Tap In]

I don't think it was ever an issue whether Cell+RSX could do something similar.

Well then, perhaps it was trivial to point it out as a named feature in the xenon/c1 combination. If there is no issue then the discussion is settled.

The difference between render target writes and MEMEXPORT is that MEMEXPORT uses no coherancy patterns to dictate the data output. For example a vertex shader on Xenon can do this

MEMEXPORT TO Address(0), Val0
MEMEXPORT TO Address(10000), Val1
MEMEXPORT TO Address(2344), Val2
MEMEXPORT TO Address(9990), Val3
And still write fragments via the pixel shader to EDRAM

To do the same thing using a conventional rasterisor would involve 5 seperate triangles (one for each memory write). Thats a vast difference for many GPGPU operations, any GPU can do MEMEXPORT like function but by using lots and lots of triangles...

It basically allows full scatter/gather memory functions, the major difference between CPU and GPUs.

I think the key difference between XB360 and PS3 integration is that, where we know both have communcation lines direct to CPU storage, we dont know if RSX can export data during a shader to RAM.

A conventional GPU can write to RAM, but it can only export pixel data and the like. Xenos can apparently send any data from within its shader array. This means you can send vectorised data to Xenos, have it proces that data, and returned the still vectorised data for use elsewhere, without having to bunch that data up into packets that fit triangle data structures as is currently done. This is what opens Xenos up as a vector processor.

We don't know what degree of data manipulation RSX has. On the one hand it doesn't really need to be a vector processor as that's what Cell's for, but on the other nVidia talk suggests they and Sony having a similar vision of the future, which might well see a more free-form data structure appear in RSX.

thank you for the clarification guys.

 

[Megadrive1988]

FLOPS are important. but they are not the be-all-end-all. they are a basic building block for how much GEOMETRY and LIGHTING you can have per frame and per second. and animation, physics,.

secondly, there are different types of Flops in the sense that you cannot compare PS2's 6.2 Gflops to the claimed 80 Gflops for Xbox.
(CPU flops and GPU flops are different)

 

[Helstar]

[Correct your posting style before you post here again . Keep cursing to a minimum and actually read what others have to say and don't run off on a tantrum when you don't fully know what your talking about .