My framerate has dropped significantly, I don't know why?

Recently, I had my laptop repaired. During that time, it was updated to windows 8.1, and I had a technician go through and make sure my drivers were correct (which I fixed and few and the rest were fine). Now, however, I've been experiencing huge framerate drop in games.

DayZ Mod, for example, now only runs at 15-25 fps when I used to get 35-45fps consisantly, sometimes 50 at peaks, now it seems to peak at ~30fps.

Any idea as to why my laptop is running this way?

Specs:
Lenovo Y410p, 64x bit operating system
Intel i7-4700MQ CPU@ 2.40 GHz
8.00GB RAM
1TB 5400 RPM+24GB SSD
NVIDIA GeForce GT755

Guest

Overheating is the common cause. Your CPU and GPU automatically throttles when it gets too hot. Get a decent laptop cooler for it, you shouldn't play games without one really. Make sure you aren't blocking the vents as well. Another issue is the fan tends to get clogged with dust, hair, etc. Or might not be functioning altogether.

Overheating is the biggest issue with laptops as the hardware is cramped and the cooling system is normally insufficient, not to mention vents being blocked while it is being used on various surfaces.

ShadowFalls