The reason I was asking earlier if this happens in only the said game is because it may not be a driver issue? It may well be a corrupt install of Black Ops. Regardless of driver version, you shouldn't be suffering black screens.
If every other game is fine then it's sure to be a corrupt install of the game and reinstalling it would be a smart move, before fiddling with drivers. If you don't have other games to test, try downloading a benchmarking program like "Unigine Heaven" If that runs properly, you can be sure it's the game and not the graphics drivers.
If you have problems with Heaven. Then look to drivers. You are complaining about old drivers still being recognised. You will need to uninstall the old ones properly. There should be a guide somewhere on how to properly uninstall drivers.
Drive Sweeper, CCleaner and safe mode come into play. This ensures no traces are left behind and no conflict of drivers when upgrading to the latest. Especially important when switching from ATI to Nvidia or vice versa.
Your PSU is fine.
