can not get computer to boot up after motherboard change.

[bethsmark]

Computer would not recognize any of the CD Roms as being installed. I changed out motherboard and hard drive. It now recognizes the CD Rom but will not boot up. I am running Windows Vista on a Dell XPS 420. The motherboard is an exact replacement. I have run diagnostics and it is saying there are no problems with the system. I changed the BIOS to boot from the CD-Rom first so I could reinstall my OS but it will not boot up. What am I doing wrong?

 

[Frisbee_68]

Where exactly does the startup process stop?

 

[bethsmark]

Where exactly does the startup process stop?

 

[bethsmark]

On the screen right after the name screen. "Initializing Intel (R) Boot Agent" It goes down and says, "PXE-M0F: Exiting Intel Boot Agent. No Boot device available"