GUID: fffffff ffff fffffffff etc..

I recently had the motherboard replaced on my lenovo box system. I am now out of warranty and am receiving very little help from them.

i7 chip.

Since that replacement was done, when I boot the system I get two hard system beeps with some flashed message about invalid serial number.

Then the system tries to find a boot file via LAN in the intel boot agent. This process takes about 1 minute until 'no startup file found' appears and windows boots as normal. The setup agent is set to "use bios boot order" and the bios boot order includes ONLY my DVD drive and my system drive. All other options have been [x]'ed out of the boot order.

During the time when the system is looking for the boot file VIA lan, I notice the string that I put as the title of this post. 'GUID: ffffff ffff fffffff' im unclear on the number and spacing of the F's, but its something to that end. Maybe this is a clue that I lack the expertise to identify.

I have no idea what to do to fix this and it's really irritating. Any ideas?

I'm also trying to re-install windows 7 from dvd. Due to the above issues, I can't figure out how to boot from the dvd. When I press F2 during the startup process I am taken to the LENOVO recovery options, which do not include booting from dvd.