Pretty much as the title says. I've had this in both Vista and now 7 using the latest nvidia drivers (and a few before this). As soon as I enable my second monitor the card clocks up to full 3D clocks no matter if Aero is enabled etc. If I disable the second monitor it'll downclock again, but I'd rather not have to do that.

So, anyone got any idea at all what could be causing it?

Probably a bug in the drivers I'm afraid.

I'd figured as much Looks like I'll be buying a bigger monitor soon, so as to not lose pixels