MikeB on 19 September 2007
@ sieanr
No its not, especially with the clock the XDR is at. At best its a little better, at worst its slower than GDDR3.
XDR measures to achieve low latencies and high bandwidth are important for the Cell's innovative design to be more effective (of course the memory controller is located on the Cell to reduce latency, high ring and local store bandwidth).
Basically the XBox 360 has gone for a cheaper design (shared 512 MB GDDR3), GDDR3 can only connect 2 devices, so the Xenon has to share the bus with the Xenos, which would be destructive for a processor like the Cell which is much more powerful than the Xenon and with high Xenon bandwidth usage then severely limits the Xenos as the 10 MB eDRAM surely isn't enough), XDR costs Sony more and would be less beneficial to the RSX. Thus the RSX uses GDDR3 and the Cell XDR memory.
Effective and peak data rates for two bus turn-arounds every 100 cycles
