I just installed avira antivirus a couple of days ago because my Mcafe trail had expired. But now my PC is running slow. I noticed it had become slow but it wasn't until today that I tried to play League of Legends that it was so bad. Really really low fps. It is not just the game, I mean even when I start the PC it takes longer than usual. Chrome opens with delay; when I try to right click on desktop and refresh, I see the small circle for 1-2 seconds before the options tab opens. What should I do?