Please Help Counter-Strike/Comp Problem

[Scruff77]

Ok i just recently upgraded my garbage pc to :

2 gig ram
nvidia 7900gs
processor fx-57
asus mobo

My counter-strike is messed up. Sometimes my shots are delayed and/or my recoil is delayed. Sometimes the player models and nades are also choppy. Another thing I dont know what could possibly cause this but When I spray a full clip of somethign it stops for like a second then keeps spraying again. I tried every interp its not that. I use 101/101/25000 its not that. My pf usage is normal, my cpu usage is low. I scanned and found no viruses. If anyone could figure out what my problem is I would really appreciate it. Also, the guy who built my comp put my old hard drive as a slave, could this have any effect? Thanks.

[cHiNgY1788]

if possible, disable onboard video
make sure you have the latest drivers installed for the video card and motherboard