It's possible that this is a driver issue, but it doesn't occur in any other games.. including Diablo 2 (also play BF3/Skyrim recently, and it's never occurred). When I open D3 my GPU will remain downclocked to 2D speeds, causing my FPS to be in the teens. I usually have to open the game 5-10 times before it finally goes to 3D clocks, at which point I can play normally.

I figure if Diablo 2 (in all its graphic splendor) causes the GPU to go to 3D clocks and Diablo 3 doesn't... then it's gotta be something with the game.

[edit] May as well give full specs from the battle.net beta tool. Since it's not included in the below, I am using nVidia driver 285.79

Operating System:
Windows 2.6.1.7601 (Service Pack 1)
CPU Type:
AMD Phenom(tm) II X6 1055T Processor
CPU Speed:
4.02 GHz
System Memory:
4 GB
Video Card Model:
NVIDIA GeForce GTX 570
Video Card Memory:
3.07 GB
Video Card Driver:
nvd3dum.dll
Desktop Resolution:
1920x1200
Hard Disk Size:
833.85 GB
Hard Disk Free Space:
523.23 GB (63%)
Download Speed:
1.34 MB/s (11.2 mbps)

Celeras,

I'm unable to reproduce what you're seeing, using an Nvidia GT 550 Ti with the 290.53 Beta drivers. The clocks only go down once I click outside the game screen like the desktop. It takes several seconds. Clicking back in the game window brings the clocks back up immediately.

Try the beta drivers if you like. I'm also using all default settings in the 3D settings in the Nvidia Control Panel except for having Multi-display/mixed-GPU acceleration set to Single display performance mode.

Beta drivers - http://www.nvidia.com/object/win7-winvista-64bit-290.53-beta-driver.html

I also play in windowed mode but all three modes were the same when I checked them.
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