I have started to recently get weird fps drops out of nowhere while playing call of duty world at war on my laptop. I was able to play the game jsut fine with no problems for half a year. I have had this checked and they said theres nothing wrong in it and its not overheating.
cpu: intel i5-4210u
gpu: geforce 840m
ram: 8gb ddr3
One thing i have noticed while playing is that the cpu usage when the fps drop happens drops with it from being about 30% usage to under 10% usage. Gpu usage stays at 99% all the time while gaming.