Overclocking 680 makes folding much slower?

[chengbin]

I just bought a GTX 680 to fold. I tried overclocking with MSI afterburner, but it seems like when I overclock, F@H becomes much slower. On stock, my whole computer uses 195W from the wall. When I overclock and fold, it only uses 143W. If I run furmark, I can see the gains from overclocking, so I'm actually overclocking my card. What's going on?

[Zagen30]

It's possible that you're overclocking it too far and that it's downclocking as a result. What are the temps like when it's folding?

[bruce]

FAH makes extensive use of the shaders but (more or less) ignores memory. Video (including Furmark) makes heavy use of Memory which uses more power and generates more heat. Downclocking your memory probably reduces heat and power-draw which potentially leaves some thermal headroom for the boost function to get more performance out of the shaders. YMMV.

[P5-133XL]

May I suggest that with MSI afterburner that you configure it to continuously monitor your clock rates, in the systray, so you can see what happens. With my video cards, I have set it up to monitor temp, clock rates and % GPU usage so I can see at a glance from the desktop what is going on with my video cards.