need pc help (et)

Yo,
I might give et a little try, but since I have installed the game and when I join a server, I get high fps drops, its a new pc but with my old grafic card(which is actually not that bad). I also have a new monitor (24").

Is that because of intel or my new monitor?

I also tryed other configs but nothing changed. It only happens when I see players.

Thanks for the help. (Written with the Phone,so broken english included :P)