Problem with friends build.. help?

[atmax1]

My friend built he's first computer with the odd bit of help from me over the phone and everything works fine with on-board graphics.

PC Spec
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i7 4770k
MSI Z87-G43
(Tried two 780s) now uses a MSI 770
Corsair Vengeance Pro Red 16GB 2400mhz(I think he picked this ram)
Windows 8
and would have been a corsair 850w PSU


The Problem
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When he puts in a graphics card games crash at the menu / loading into the game, the only game that didn't was counter-strike source. Any ideas as to what it could be? we have tried 1 ram stick at a time, 3 different graphics cards and 3 different drivers... updated the bios etc I haven't got him to drop he's pc off yet could it be he hasn't seated the graphics card properly? (looked ok by the picture he sent me though)

 

[atmax1]

I tried that everything was fine, still crashed with 1 ram at a time and memtest reported no errors could it be the motherboard?

 

[atmax1]

He can get into windows and do anything but play a game, I made him make sure everything was plugged in properly and windows does not crash at all, there is no blue screen just when he goes to enter a game the games freeze and he gets the pop up sometimes saying to close. At the moment he is using the latest 337.50. I didn't see any errors but when I get hold of him I will look again.

 

[atmax1]

The problem was a faulty motherboard.