Display port help

[farmerboy-86]

Hey guys so I just brought a 1440p 27" monitor been using hdmi but just changed it to display port as I found cheap one in black Friday in my local computer store.

anyways the screen keeps going black while gaming for a split second then fine again randomly happens

I have r9 390 overclocked
On windows 10
Latest drivers

if that helps, works fine on hdmi and dvi

Any help appreciated as I'm new to display port

 

[farmerboy-86]

turns out now doing the same on hdmi duff monitor me thinks even reduced gpu overclock doesnt help

 

[farmerboy-86]

Gpu is msi r9 390
Monitor is Acer g277hu 2650x1440p
Cable is from maplins £25

How do I change from 1.1 to 1.2 as I'm new to display port cables

 

[farmerboy-86]

Yeah tried both cables and both go black
Have reinstalled drivers gone back to beta ones which worked fine with old monitor nothing helps

Hdmi is also doing it so I think monitor is problem gonna try my old one will report back