Minidump analysis

Hi

I have an old pc that i have to get fixed it blue screens everyday randomly. I would really appreciate it if someone could look at the minidumps and tell me whats wrong. I downloaded all new drivers from manufacturers sites and it doesnt help.

Heres a zip of all dumps.
http://www.mediafire.com/download.php?mjzzk3tn4jm

Sorry to ask but i am in rather of a hurry.

Hope to get a response soon.