Why is my games running slow?

Hello. Me and my friend opened up my ASUS G11CD pc and removed some dust. We did not use a vaccum cleaner but a hairdryer on the lowest setting and now almost all of my games are running slow. They are lagging extremely much and I have tried to use the lowest settings but it lags anyways. I have turned on my pc fan to not have the pc as dusty and the AEGIS III app says it’s the optimal. I have emailed ASUS customer support and am currently waiting for a response. Please respond to this as soon as possible.