MikeB on 29 November 2009
@ Kynes
22.4 GB/s is not a high bandwidth chip
That's the same bandwidth the Xenos has to its memory but has to share with the CPU as well.
The PS3's Cell processor has a dedicated bus to XDR.
It's also worth noting the RSX can access the XDR/Cell simultaneously together with the graphics memory if needed, considerably upping potential bandwidth.
If you confuse the Xenos' daughter chip's internal bandwidth, then remember the Cell has a higher internal bandwidth and you have to consider the tiling issues involved when rendering in high definition. For example would it have been beneficial if the Xenos had twice as much internal bandwidth but only 1MB of daughter chip memory? I think not.
If you are so smart as you say you are, this may clarify things for you:
http://en.wikipedia.org/wiki/File:X360bandwidthdiagram.jpg
