do you have an on-board gpu? i do, so whenever my fx5200 messes up (worryingly often) i just plug the screen into the onboard. Try that if you have one, then you can know whats causing it (if it doesn't work, you will have to pay for a new pc, if it does, you will have to pay for a new gpu (unless you have an amazingly good onboard) so this really isnt good.
you could try cleaning the gunk out of the fan, threaten it, break into a mates house and swap gpus with them etc. etc. if none of them work then i dont know (in the uk, its a bit easier, you just pretend to be very dislexic, and the government pays for all your computer supplies

)