Main Monitor flickers on and off when I startup computer

[SuicidalCookie]

This only started happening a week ago. whenever I startup my computer and log in out of my 3 monitors my main centre monitor constantly flickers on and off with glitch lines appearing in it. the quality is also worse like the resolution has gone down even though it says its at the normal resolution. I fix the issue but doing a clean install of the graphics driver. What could cause this to happen every time I boot up my pc though? Or if I wait 5 minutes it fixes itself and all 3 monitors flicker off and on and then its all good and fixed?

Thanks

 

[Phillip Corcoran]

Try re-seating the GPU.