wierd gpu glitch

[Devryd]

Hello Guys, 

I am having a wierd glitch with my GPU. It is a gtx 1070 gaming x by MSI. I have 2 Monitors connected, 1 over DP and one over DVI. Now to my problem: My main monitor, the one connected over DP sometimes gets a blackscreen. This happens randomly and i can't find the reason for it. It just turns black for a second or so and then continues to work fine.
I also have checked it with another Monitor over HDMI. Same thing, random blackscreens, just not over DVI. Also while in bios or posting, the system uses the DVI monitor as main monitor and i dont know how to change it

If you have any idea what might be the problem, please tell me

[Juular]

It's low-quality display cable most likely, poor shielding, thus susceptible to electromagnetic noise.

[Devryd]

But why does it happen on two displays with two different cables? The odds of two bad cables are pretty low, aren't they?