Your AGP may have a problem

Hi,
I have no signal on my monitor and I have a voice tell me my AGP may have a problem. It has happend before when I moved the computer and installed a new wireless lan card. led on motherboard flashing next to vga slot and re boots when ctrl alt delete
I have firewire going to the monitor and the serial port is part of the Video card .
Video card is ATI.Do I replace the vidio card and hope for the best? the fan is working on the video card as well.
Help this is doing my head in

Cheers

mat