Fluctuating FPS

Hello,
Since ~2 weeks ago I noticed that my FPS continously drops to 30, and then goes back up to 50 again. I have no idea why this happens, and it is extremely annoying. When I play salem, it uses ~ 30% of my processor. Memory usage stays at ~ 40%. So I do not think the problem is my laptop.
I have no idea what the problem might be, and as I said it is extremely annoying.
Is there anybody who might have an idea what the problem is?
Since ~2 weeks ago I noticed that my FPS continously drops to 30, and then goes back up to 50 again. I have no idea why this happens, and it is extremely annoying. When I play salem, it uses ~ 30% of my processor. Memory usage stays at ~ 40%. So I do not think the problem is my laptop.
I have no idea what the problem might be, and as I said it is extremely annoying.
Is there anybody who might have an idea what the problem is?