Gateway cpu has 3 long beep after owner change bios wont boot!Can anyone help?

My friends cpu now has 3 long beep after he accidently change setup due to not finding his recovery disc for vista and after changing bios cpu just beeps 3 long and and get no video or anything after beeps to boot. How can i recover the bios setup to attempt to reboot with disc he now has foundGateway cpu has 3 long beep after owner change bios wont boot!Can anyone help?sounds like memory problem remove the memory and video card wipe the contacts with clean cloth %26amp; put it backGateway cpu has 3 long beep after owner change bios wont boot!Can anyone help?Check out the site below-it all depends what BIOS you have, for the Beep Codes.