Monitor/video issue?

I just built my first computer, and I know nothing about them.

My issue is when I zone the art/loading screen shows then it goes black for a few seconds re-shows then the map loads like normal.

and

When I click on a Youtube link it opens it in a new tab, the screen goes black of a few seconds then the video starts playing in the new tab, then when I close that Youtube tab the screen goes black again for a few seconds then the original tab loads.

Does it in full screen and windowed.

Resolutions all match,Graphics card, Monitor, In-game, 1920x1080

Updated all the drivers i can think of.

Tried using DVI and HDMI cables, same difference.

Win 7 x64
i5-2500k
8gb ram
ASRock extreme4 MB
Nvidia GTX 560
Acer 23" s232hl 1920x1080

Adobe flash player setting: Enable hardware acceleration

I unchecked the box, no black screen for Youtube.