Hi Goober, I hope this might help.
I had a similar problem to what you are experiencing and here's what I did.
Grab yourself a free copy of Driver Cleaner Pro. You can just google it and get a tonne of hits. Uninstall all your Nvidia stuff through control panel and that goes for everything, stereo, wdm, 3d drivers, physx etc. Reboot for good measure and run driver cleaner. Ask it to delete everything it can find related to Nvidia. Reboot and reinstall your nvidia drivers.
This should give you a nice clean driver install and hopefully solve your problem. Will check back later to see how you went.