Replies to post #49109 on Advanced Micro Devices Inc (AMD)

[fastpathguru]

Lack of a ccHTT interface would be a significant impediment to implementing an A64 dually.

fpg

[pgerassi]

Dear Mmoy:

Simple fact that none of the A64s have a Coherent HT link and that they have one noncoherent 16/16HT link for IO. An Opteron 1xx has 3 noncoherent 16/16HT links. An Opteron 2xx has 1 coherent and 2 noncoherent 16/16HT links. An Opteron 8xx has 3 coherent 16/16HT links. You need at least 1 coherent link in each CPU to pass cache coherency information back and forth.

Pete

[CombJelly]

"Why can't A64 do dual processor?"

Because AMD made a deliberate decision for them not to have that capability. They only bonded out 1 HTT port for Socket939 and Socket754. And since a processor that doesn't do I/O is a room warmer...