Have been asked to look at a PC for a friend. When you turn it on the computer appears to boot up but you don't get any output to the monitor. Have swapped the AGP card for a PCI card and it is still doing the same thing. If once the PC is on you 'wiggle' the graphics card you can tempt it to work but as soon as you turn the PC off and back on again it fails.
Bit stummped as to what it could be, though am heading towards a failed mobo. Any ideas?
This is a VERY confusing problem! You've tried both PCI and AGP card, both only work by wriggling. You've tried a different monitor, and the problem is still there. The only other thing I can think of is a motherboard problem such as a crack in a track, a dry joint or a short to the case. Wriggling the graphics card also flexes the motherboard. You could try unscrewing the motherboard from the case and placing a sheet of card under it. I have even known a motherboard with a pin of a surface mount chip that had lifted from the track. Resoldering cured it, but the chances of hitting on the right pin are very slim.