HELP!!!!

ive a dell gx280 and i got a nasty virus. ive removed most of it but, after that ive lost all my drivers for network adaptors. No LAN, Wireless or bluetooth. Ive tried to install the drivers that i downloaded from dell but its no use. I was wondering if i can do a factory re-set on it and then try from scratch. i dont have a back up disc. when i go to where the internet connections are on it there shows only one dial-up. before i had about 4 or 5 different options. on device manager all the connections now just have a yellow exclamation mark beside them. Ive been at it for 3 days now and im getting very fed up with it.

many thanks in advance

  neil