It seemed that when I first started playing Rivals, that I could handle low in 1080p with my Zotac GTX 650 TI. But after the sixth start-up, it got freaking laggy. I had to downscale to 720p so I could handle the graphics. Do you know if there is any reason my GPU was fine before, but can't handle it NOW?

(P.S. if you have any setting tweaks or edits so i can get better performance and can play in 1080, that would help! )