i have a problem

[SniperKiller]

So I have a problem on my computer it had a virus in the registry and i got rid of now when i got rid of it i try to play counter strike and left 4 dead every time the game will make the team chat messages and team switch menus and buy menus pop out on its own and switch me from teams on its owns well as turn the sound off on my computer off compeltely and when i try to type in game it will type on its own a bunch of letters and numbers. I think its the virus in my mother board and im trying to get rid of it by reseting my cmos but idk how to do that. When i try to go the cmos menu it only takes me to the bios settings when i press del

I have
Asus A8S-X motherboard
2 gigs of ram
Amd anthlon 64 X2 dual core processor 3800+
Nvidia Geforce 7800 GT


Can anyone help me it would be much much appreciated.