My CPU usage is very low and RAM usage also about 10%, but my computer is really slow while I'm writining on facebook, PC config I7 3770k / 16gb ram corsair / evga geforce titan x / ssd 120gb / I have no problem with any other part, just on facebook, take 2~3 seconds to my words appear idk why
This should probably asked in the Flash Player forum. This forum was for the Flash Catalyst program.
With that said, it might just be Facebook and all the elements it uses. One quick test would be to disable Flash in your browser and try out the FB. If it is still slow, then you know it is NOT the Flash Player.