Originally Posted by RawFoodPhil
The lack of Vram could be causing you to bottleneck.
Yes, but in theory it should affect both cards the exact same way. I monitor vram usage on both my cards all the time, and it's always exactly the same vram usage on both cards. I've also created scenarios where I was exceeding my vram capacity, and it didn't cause my usage to get wildly out of sync like this.
Originally Posted by alphamanG
I experience this with GTX 570s in SLI with dual monitors also recently after switching my cards around into a new mode (16x/8x)
Check your PCI-E config. Are you running 16x/8x or 16x/16x? I never had problems in 16x/16x and now all of a sudden I am in 16x/8x. Only difference is using a 3-way SLI bridge instead of a 2 way...
Mismatched PCI-Ex slot speeds could definitely cause gpu usage to be slightly different on each card, but I doubt it could cause a discrepancy of this magnitude. That's a good thought though, and the possibility further explored!
Originally Posted by Emmanuel
The lack of VRAM could indeed hold the usage down, I don't think your CPU would be a bottleneck. Maybe you need to feed your IOH more voltage. It could also be a driver issue, I remember in Bad Company 2 sometimes the usage would suddenly drop to 40% for no reason and after a minute it would go back up. I haven't noticed that in BF3 yet but I do get other kind of lag lol.
See my first reply. It could, yes, however, it should affect both cards identically, not cause one to be dramatically lower like we're talking about in this case.
My first suggestions are: disconnect the 2nd monitor, see if that fixes it. Also, you aren't running in Windowed mode are you? If so, don't
Also, dumb question, but ... you have double-checked that that SLI is indeed enabled, right?
Also, the one w/the higher usage doesn't happen to be stuck at low-power 3d mode by some chance (which is 405MHz on my cards, not sure on a 460)?