Is there any particular reason that the CUDA miner would only perform at maximum khash/s if its CLI status window were the foreground window? I'm seeing consistent drops from 16000khash/s to 6000-9000 khash/s when the window is not in the foreground, even if absolutely nothing is happening in whatever window is the foreground (even away from the computer).
System: Windows 7 Enterprise 32 bit, 2.9ghz Core2Duo, Geforce 9600GT, 3gb RAM.
I'm another person that has issues with the CUDA miner speed dropping significantly if it isn't the currently highlighted window (109000 khash/s down to around 16000 khash/s). I really like this miner, but I pay ~100khash/s opportunity cost to actually use my PC. I run the 4way miner at the same time and see no slowdown when it isn't the active window.
I have W7 Professional 64-bit, mining on a gtx 480.