Random Fps drops in game



I bought a MSI Ge620dx around christmas. Around 2 months ago my Motherboard stoped working so i sendt it in for repair, and got it back without any problems. But recently I have gotten random Fps drops when playing games (Guild wars 2, Skyrim, Fallout: NV). I play for 2 min in 40-50 Fps but then it drops to 5-15 fps and it stays there for 5 sec then back to 40-50 fps!

What i have tried:
Cleaning laptop Gpu and Cpu.(I dont think this is the problem becuse the lag is still there when my Gpu is at 60c and Cpu is at 70c)
Disableing Anti Virus. (Did not do anything)
Disableing unwantet Processes. (I got 6 Gb of ram, Is that bad?)
Updatet drivers. (Helped on getting more Fps but the problem is still there.)

Pc Specs:
Intel Core i5 Processor 2430M 2.4GHz 3MB L3 Cache
Chipset Intel HM65
2GB DDR3 Memory
640GB SATA hard disk
NVIDIA GeForce GT 635M Graphics Optimus
Screen 15.6 "1920x1080x
Interconnection 802.11bgn wifi and Bluetooth 3.0
USB 2.0 ports, USB 3.0, HDMI, D-Sub, Audio In / out, Ethernet
Card reader
Optical Drive DVDRW
4400mAh Battery
Size (mm) 383 x 249.5 x 37.6 ~ 32.3
Weight (kg) 2628

Hope you can help, I realy want to play some guild wars 2
Umm, your laptop is 2.6 tons? kinda doubt that...

Anyways, random drops could be very hard to track down. best thing get a monitoring program that has logging on something, and compare it with a logging program that can record fps.

How long do these drops last? if it's only 2-3 seconds then it's background processes or hdd. If they are longer than that, you have to look at the said monitoring above, it could be that your CPU hits 100% utilization due to some process and thus fps drops or you get to some temperature level where it throttles back until it cools a bit. Or it could be that your GPU is running out of vram, takes a few seconds to push things it doesn't need from the memory and load the needed information.

does it happen with all the games or only some?


I think i fixd it!
I had disabled Defragmitation -.-
But thanks anyway :D