I have BF2 installed, with the patch, and every time I start it up, the screen goes black and makes a clicking noise, like the monitor's been turned off, does it again, then it just exits out of the game.
Anyone know what the problem might be?

You probably do this already,but go into task manager and kill any processes that aren`t absolutely necessary.Same goes for services.msc.Less is more,as they say.
Interesting link - http://www.tweakguides.com/BF2_3.html