Computer disconnecting from monitor

Lately i'v bern having a weird problem where my computer disconnects from the monitor as in screen goes black and the popup for (No Signal) appears on the monitor. Its only happened while browsing/casual use of computer so far. And when it does happen my computer wont turn off via power button. It wasnt a frequent thing up until recently now it just happened twice in the last 10 mins its quite annoying and i dont really know whats causing the problem.

Rig:

Amd fx-8350 @4.0 ghz

Gigabyte G1 980ti

8gbs Corsair vengence ddr3

asrock 970 extreme4 mobo

Corsair CX750w psu

Kingston Hyperx fury ssd 120gbs

Western Digital 500gb hdd

BenQ XL Series XL2411Z