Originally posted by: hans007
depends on how you look at this.
the xbox 360 gpu has 36 unified shaders and i think a 256bit bus. it also puts out more heat than the sun. its basically a x1900GT .
It has 48 unified shaders, not 36. Each of these shaders is comprised of 4 ALUs that can execute a single operation per cycle, so that each shader unit can execute four floating-point ops per cycle, giving 192 shader ops per clock cycle. You cannot compare these shaders to straight pipelines of X1900 derivatives. 360's gpu is based on R500 gpu which has nothing to do with R520/580 of X1900 series. Additionally, the gpu has eDRAM which allows it to have 4AA at supposedly minimal performance drop.
I am not understanding the argument about theoretical comparison between 8600GTS and what would 360's gpu perform like in a PC. Who cares about theoretical performance? Look at PS3 cell which was touted as way more powerful than 3 core Xbox360 PowerPC cpu. But in the real world unless you can utilize that power, it's theoretical peak is useless. Similarly, if 8600GTS cannot deliver equal performance in Oblivion, Bioshock, etc., for all we care it can be 5x more powerful but in the real world if it can't produce equal or superior image quality at playable framerates, it's inferior.
But if you really want to compare numbers, here are 2 key figures:
Shader Processing Power
8600GTS = 139.20 GFLOPS
360 =
240 GFLOPS (10 FLOPS x 48 shader pipelines x 500 MHz)
Pixel Fill Rate
8600GTS =
5.4 Gpixels/sec (675mhz gpu x 8ROPs)
360 = 4.0 Gpixels/sec (500mhz gpu x 8ROPs)
Source: Wikipedia.
Since games continue to be more and more shader intensive and the performance advantage of 8600GTS in texture fill-rate is not that significant, 360 gpu is more powerful --that is before you even consider the 4AA advantage offered by the eDRAM chip.
But let's forget the theoretical analysis above. If you had a chance to play Ace Combat 6 demo, DiRT, Gears of War, GRAW 2 or Fight Night on 360, you'd realize 8600GTS
has no chance at all to match the graphics produced by the console.