DVI Problem Please help

[bakes0310]

Basically my brothers computer has been playing up for the last 3 months. When he plays most of his games he will get a black screen saying DVI No signal.
He has looked at the wires and hes done a system restore but he still has the same problem.

 

[bakes0310]

Not much info to go on there. Does it only say "No signal" when playing games or while doing anything else in Windows? Is the PC still on?! Have you got another monitor you can swap it over with to see if it's that or the PC?

it says no signal and yes the computer is on. And also it only happens in some of his games, and no i he hasnt got another monitor to try it on.