Hello, I'm posting this in order to find some help, I fully appreciate any kind of answer that relates to my problem, hopefully people with the same will find great help in this post. Here I go, I own a laptop : Travelmate 5742g. Intel Core i5-480M 2.66Ghz (can be boosted up to 2.93Ghz with turbo) Nvidia Gefore GT 540M 1024MB VRAM 4GB DDR3 memory 500 GB HDD (not even half occupied) I used to play games like Mafia 2 / Assassin's creed 3 / Battlefield 3 and such perfectly with medium / high settings without problems, but now regardless of the game's requirements, It seems that after a period of time the games start lagging, dropping my fps from nearly 45 to 15 / 20, I suspected that my fan was dusty so I cleaned it up but the problem still persists, I'm asking you to help me find out the answer for those lag spikes, Is it a malware infecting my pc ? if so what are the tests I should run ? Thank you so much for you replies, god bless you all.