Originally Posted by JCPUser
580 triSLI is slower at $500 more... Very surprising.
At first I though it was a CPU bottleneck crippling the triSLI 580s given that they are only using a i7 920 @ 3.6; but they are getting much better frames with the triFire set up with the same CPU so that can't be it. Maybe a vRam bottleneck for the 580s and surround res and 4x AA. That or maybe CFX scaling is just that much better than SLI scaling...
EDIT: Looking more closely, for 3/5 games the SLI and CFX setups give the same FPS so maybe it is a CPU bottleneck after all
Bottleneck, eh. Myself from the very first page in this thread
Anyway, good re-test. Nvidia pulls head as expected for the $400-$500 premium. AMD is better in some games in terms of $/perf and it others the 30% increase in cost almost gives you a similar increase in performance.
About the loss in performance with the AMD set up in some games... I think it points to the crossfire bridge bandwidth issues at eyefinity type resolutions. In the first set up, there was a total of 36 lanes of pci-e bandwidth (16,16,4), but it the second set up there were only 32 lanes (16,16 or 8,8,8,8). If I remember correctly, CFX uses empty pci-e lanes to make up for the shortcomings of the bridge. In the first case the 4x is empty, however for the re-test all the lanes are being used by GPUs. I wonder if that explains the huge drop in F1.Edited by JCPUser - 5/3/11 at 6:25am