I have had another PC problem pop up on me.

Earlier tonight, my screen started flickering increasingly aggressively and went completely blank around half an hour ago, and nothing I can do can make it work again.  The main PC can still run, but I can't use it. If I restart it, the screen will work a couple of seconds after I turn it on, then go blank. I bought the PC in February 2013, and the graphics card is less than a year old. The monitor is around ten years old.

Boot into the bios and change your graphics card to VGA, or supervga if that's the only option, just don't pick the graphics card. Or boot into safe mode, it will do the same job and not load the graphics card. Now see f rs stable, if it's the cards buggered.

Turned out that the monitor had died, I was able to procure a new one for £15.