Re:AMD vs Intel (Score 1)

It's probably because of HyperTransport and floating point computation performance. I think HyperTransport made it easier for supercomputer vendors like cray to build better interconnects and traditionally opterons was a bit better at floating point ops. Also, opterons have 64Kb L1 caches where I think comparable Intel processors had 32Kb L1 caches. But this was all a couple of years ago ... the next generation of the fastest supercomputers will probably be Intel based.