Gainward GTX 750Ti video card doesn't work in 1 of 3 PCs
I have 3 virtually identical PC's and just bought 3 new Gainward GTX 750Ti video cards for them.
The problem is that the new card type doesn't work in one of the PC's and all I get is a black screen from start up.
The PC with the problem was running a Gigabyte M61pme-S2 video card before which still works fine in that PC and the onboard video also works fine so there's something about the new card and that machine that is a problem, even though that combination is fine in the other identical PC's.
Things I've tried so far:
-I've tried the same card in other PC's and it works fine.
-I've tried putting a higher voltage PSU in the machine with the problem.
-I've tried removing the BIOS battery for a minute to reset the BIOS and also selected default factory settings
-I've tried a new video cable and new monitor
-I've tried running through all cables out of the card ie. HDMI, standard etc
I'm not sure what else to try.
Can't be a driver problem because it doesn't get to that stage.
Can someone please offer some advice on what the problem is as I doubt I can get a refund on a card that will test as working.