Graphics card problem

[Andrespetmonkey]

I recently bought a gtx 650 card for my computer, at first I was very pleased with the performance and I was playing World of warcraft in high settings and league of legends at around 100 fps which is great, Although a couple days ago my games started to run with a lot of lag and fps drops in the high settings, I put my settings to minimum on all of my games and there is still noticeable lag and low fps. I haven't downloaded or installed anything recently that could be effecting the games.

Here are my computer details:


Thanks