Hi,
So lately my pc has this sudden and random FPS drops,
and this seems happens with every game i play,
before i used to play Left 4 dead 2 with the highest settings smoothly
now after 3 - 2 minutes in-game my FPS goes from 71 to 15. D:
I tried to reformat my computer to see if it could fix it, but the same thing
keeps happening, is there a way to fix it :/ .

Howdy Harpuia and welcome to PCHF

Have you tried updating your drivers for the gpu? Also it could be heat. Download speedfan and let us know what all the temps are. http://www.almico.com/speedfan446.exe

Here is the GPU temperature

Temps do look high

How can i reduce the temperature?

I see that this is a laptop?

yes it is, got it on November.

Iam not familiar with laptop hardware&temps so cant help much,but when you are playing do you have the laptop on a flat surface like a table? because i see a lot of people on their laptops on beds and on their laps and that will make it overheat

I always place it on my wooden desk .

Many laptops have an ease of access fan, where you can get at the fan blades with only a slide of a lock, or 2-4 screws at most (Unless it is an Acer laptop which seems to enjoy putting the fan in the least convenient place) Your issue sounds exactly the same as one I used to have, and removing the dust buildup in the fans solved it instantly for me. Also remember to keep your wooden desk lean and keep the area where the hot air is being pushed out of clear.

I have an acer laptop :/
so if i remove the dust, it will fix the problem?

I know it did for me, but I would strongly suggest looking up an online manual for dismantling it enough to reach the fan, or if you are not comfortable with that have a professional do it. Unless your Laptop make is different than the 2 that I am familiar with, and you can easily access the fan