PC crashes when gaming in SLI

[removinggoose]

Hello, i recently purchased a second gtx 970 to run in slip with my current one however whenever i open a 3d application such as a game, the computer will shut off after about 1 minute and reboot itself. I used fur mark to test the cards and when in sli, the only way the pc wouldn't shut off was if anti-aliasing was set to 8x. Tried forcing applications to use 8x and 16x in nvidia control panel but not working.

Specs:
windows 10
Intel i5 4690k
2x gtx 970 in sli
Sabertooth z87 motherboard
Silverstone 750w silver certified psu
corsair h55 cpu cooler
(nothing overclocked)

 

[DaleTheWhale]

What drivers do you have?
Possibility that the new 970 could be faulty, does it work on it's own?

Any crash dumps?

 

[FatRakoon]

I would try each card on their own first.

If they both seem to work, then I would consider the power... Even if you have good power, are the connections good?

Is the bridge ok too!