random black screen

ok this is like the 4th problem with my computer i have posted here, i fix one thing on this computer and another pops up..

totally random intervals, but approximately once every minute or so, my screen flashes black, for like 1/2 of a second. it looks as if it turned off and turned back on, it does this using internet or playing a game or whatever else you can think of, umm ok it just did it and my comp seemed to freeze for 2 seconds afterwards.... its done it 3 times so far while typing this post. how do i stop this ???

 

Start by trying another monitor. If it still happens, then try a different video card. Most likely it's one of those two. Maybe your video card is overheating... Try lowering your refresh rate as well. To do that, right click on the desktop, go to properties, then settings..then advanced, then monitor. try that for now.