I have an evga superclocked gtx 550 ti and when i play tf2 i get around 300 fps when im playing with no one
when i join a game with like 20 ppl it can drop all the way down to the 100's
this happens even worse in counter strike: source
same thing but if i join a game with 20+ players it can drop into the low 30's to 50's
gtx 550 ti
8gb ddr3 ram 1333mhz (is this why? or is ram not a big deal?)
amd fx 8120 overclocked to 4ghz
Frame rate dropping when more players in MP screams cpu botteneck.I have no idea how good that cpu is,but from what i heard its no good for gaming.But CS drop is rather drastic.Your gpu is fine otherwise it won't have pumped high FPS when on one is in server.Also CS source is very old.What happens in CSGO?
You are doing just fine with the games that you are playing. I would say its good that your frames drop a little bit because at the frame rate you are getting in those games if you get into the 300's would lead me to believe at some point you would experience tearing where the game can not keep up with the horsepower that you are throwing at it. Your GPU is not faulty I would say you are where you ought to be with the titles you are playing.