First I'd disable any tools that may be installed along with the graphics card's driver, i.e., stuff that allows for screen tilting, etc. I'd also temporarily disable any applications that hook into the display system, e.g. video conferencing software (such as Skype), remote management applications (such as VNC), or Windows themeing applications (such as Window Blinds).
In general, I'd also run the affected system with only the minimum amount of background processes and services (you can use msconfig to disable most of these and numerous guides as to which services should not be tinkered with are available online).
The docs included with the graphics card driver should give you some overview about what additional tools get shipped / installed along with the driver.
Again, let us know what you find and we'll take it from there.