We have a Dell C521 and got tired of Vista. We formatted the hard drive and installed a previous version of XP. We were getting the downloads from the Dell web site to bring the computer up-to-date. During the download of bios it locked up and did not download. When the computer was restarted it started with a series of two short beeps and 1 long. The monitor showed "no signal input check video cable. We plugged the monitor into our laptop and it is fine. We removed the battery to try and reset the bios. We don't know what to do at this point since we can't see the error message on the computer. Is there something we can do to try and fix this ourselves?