Im having a little trouble with my video card drivers, im using a 6600 TD 256 meg video card and having no problesm what so ever with driver 77.72, but when i goto get any driver higher then this number and goto to properties, settings, advanced the screen at this point goes black like its switching off then once the Plug and Play window comes up for the Nvidia card it comes back on.
Also when i goto play games etc it tells em the frequency is out of whack and i cant play the game even when i use the lowest frequencys and 800 x 600 resolutions, if i roll back to 77.72 driver i have no problems at all.
Have you properly uninstalled the 77.72 drivers before installing new ones? You'll find graphic card drivers can be a little funny sometimes if the previous driver is not uninstalled correctly.
I'd suggest to have a read and search through this forum and take a look at the top sticky in this link too.
Check your monitor drivers are installed correctly as well because either from the video card or monitors perspective if theres a inconsistancy or frequency it cannot handle you will find you will have problems.
Is your graphics card getting the right amount of power to it? (does it have a power cord plugging into it? If not rule this one out)
Some other things to try or future troubleshooting tips.