My new pc got slower and i dont know what to do next

Hello,

I just bought my system 3 months ago from a website that provides well built gaming pcs.

What i am playing is simple games like, CS Fifa LOL, but lately i realised that i was getting low FPS on games and i was getting FPS drops. And its getting worst after some minutes, so i wanted to check if temperature is ok but its always ok. its arround 60-40 degrees. its not only about gaming, when i search in google i feel that it got slower. บาคาร่าออนไลน์

I decided to format my OS and download new one and install it, well i did it but my pc is still slow.

I changed the electric socket already, i dont know what option i can do expect going to pc service, can you please help me guys ? i dont want to spend time and money on service i am student please give me ideas so i can fix it by myself :/