Windows 7 Desktop Position

I've had a problem for a while now, with my secondary monitor's desktop being offset ~1/4" to the left. I've tried every combination of settings in the Nvidia Control Panel, but none changes this in the least. In fact, the control on the Position tab doesn't seem to work at all. It's not a problem with the graphics card, because it is the same with two different cards that I've tried.

I suppose that it might have to do with the driver, but the last time I updated it, the problem remained constant.