Advanced Micro Devices Inc (AMD)

[pgerassi]

Elmer:

As usual your claims leave a lot to be desired on accuracy:

Top current 2P Opteron 2384 SPECfp_rate2006 score is 118/105, not 108/105:

http://www.spec.org/cpu2006/results/res2008q4/cpu2006-20081024-05684.html

Only current 1P i7 965 score is 86.1/82.9:

http://www.spec.org/cpu2006/results/res2008q4/cpu2006-20081024-05710.html

Only current 1P i7 940 score is 82.3/79.2:

http://www.spec.org/cpu2006/results/res2008q4/cpu2006-20081024-05714.html

That is a 3.2GHz and 2.93GHz desktop CPUs with non ECC desktop memory, server memory will be slower and SPECfp does not scale at 100% with CPUs, even the much stronger glued IBM Power6 CPUs. I7 based Xeons won't get 2X the 1P i7 2.8Ghz score. But scaling to 1P 2.8GHz i7 Xeon EPs from the above two scores gets 82.3 - (86.1 - 82.3)*((2933 - 2800)/(3200 - 2933)) = 80.4. Using Opteron scaling from 2P to 4P as a basis, 80.4 * 210 / 118 = 143 less what the slower ECC registered memory drop will be. I doubt it will show more than 130. Far less than the claimed 160 (likely some silly 2x estimate from a 1P 2.8GHz score).

Still that isn't too bad, being 130 over 118 assuming that getting cache coherency to work won't drop scores too much (none needed with 1P being all on one die). 10% more score for 4% higher clock. Although by the time i7 Xeon EP shows up (currently thought to be Q3/09), Opterons will be on a new AMD server chipset and be running HT3.x speeds and dual HT links between the CPUs on the 2P configuration. That might make up all (even possibly more) of the difference in SPECfp_rate2006 results. Also the Opteron SE variants will be out by then which would get to 2.8GHz (238(6,7) & 838(6,7)) or even 3.0GHz (239(0,1) & 839(0,1)). And AMD might decide to pull in DDR3 into 2009. The advantage would be Shanghai well over i7 Xeon by then.

BTW the top 4P Opteron 8384 score is 210/188:

http://www.spec.org/cpu2006/results/res2008q4/cpu2006-20081024-05686.html

Pete