Screen blinks black when I click

Whenever I am in game or getting ready too my client, for the lack of a better word, shits itself. It will not respond in champ select then if I can get a champion when we are loading the screen will blink black. When I am in game however only when I left click does it blink but since that is how I check health, mana, and energy I cant get out of that. I also buy in the shop with my left mouse button. I thought that it was a virus on my computer but I just factory reset my computer to fix it. What should I do now?