Vista - Hardrive works fine now, but no monitor,keyboard or mouse activity

Hi all this is my first time posting anything anywere, here goes on 9-4-08 I clicked on a link to a program and as usual vista wanted me to approve it so I did, my antivirus program went off with a high threat and I thought it stopped anything from happening however after I removed the bad stuff with the AV program I noticed my computer would crash to blue screen every few minutes or so.
So I quickly became frustrated I tried repeatedly to used the vista cd to restore it but it would crash in the middle of the process. Next I checked the Dell support link on my desk top and it scanned the computer for any hardware or compatability issues and said I needed to install bios update.So I downloaded it ,all was ok at this point , when I began installation it completed about 25% then crashed to blue screen again . Now I am banging my head on desk... well I try to restart computer and I now have nothing at all ,no monitor stays blank,no keyboard, no mouse CD drive runs and flashes and the little #4 light on front of tower stays lit now but no HDD activity .
So I remove my HDD and install it in my sons E521 , we have same computers, and it went back to crashing to bluescreen. So now I experiment with boot sequience and boot from cd first then I just had windows vista install cd in drive and restarted computer, and that seemed to take care of that problem , however when I put my HDD back in "my" computer stall nothing ? ? ?
Now does anyone out there have any ideas ? I am thinking of trying to burn an install for bios on a cd and trying that to see if it will boot up but I am kinda scared of bios anything now.

Hi, roadan1971, and welcome to the forums.

It sounds like your BIOS was in the middle of being updated (colloquially called flashed) when it died. You'll need to contact Dell tech support and tell them exactly what happened, and see if they know of a way to restore your computer's BIOS - else you'll have o pay to have it replaced.

Well since my post I contacted Dell support and they were very helpful and they informed me that I infact need to replace my motherboard ,however my computer is only a year old so they are comming out for free in 3 business days to replace it.
thanks for any help you guys did though

Interesting fact for the day: Dell resides in an alternate universe where the business day is 73.5 hours long. We must be patient with them.