Duh, the 256GB/s is to 10MB of EDRAM. It's basically a glorified
framebuffer. How many textures can you store in 10MB? I don't think you
can even process ANY form of AA at 1080p in 10MB (hint AA involves
sampling MORE pixels than are acutally present, some forms of AA
require 6 times the amount of data per pixel, per color, to be useful
it should be 4 times the number of pixels present [which for 1080p
won't fit in 10MB of anything). Guess you've got a lot to learn don't
you?
I refer you to my original post - which I have handily pasted below:
"I'm not an XBox360 dev but I'd say the major problem for the getting
the 360 to do 1080p in games will be graphics mem. Bandwidth is
something the 360 has plenty of. Once you up your screen buffers to
1080p you need a serious amount of graphics memory - 8MB for colour
buffer, 8MB for 32bit Z-buffer.
Now I'm not sure about how clever the 360 GPU is and whether it does
fancy tiled z-buffer stuff, but you can rest assured than any new title
which wants to use proper 1080p in game is going to have to make some
sacrifices somewhere. The 360 only has 10MB of 'proper' graphics
memory, so there are going to have to be some clever multi-pass or
tiling techniques needed to get 1080p in game. MS do seem to have been
able to coax 1080p out of the graphics chip but that doesn't mean that
it can do it without a fair few compromises."
I'm bored now - goodbye.
