Upgraded CPU - now won't boot

[Lethaltoast]

Hello, I upgraded from a Celeron 2.66 to a Pentium 4 3.8.  The system
recognizes the new CPU but will not boot. I can get into BIOS setting
but as I exit it remains on the screen that shows "PCI device listing
..."  What do I need to tweek in order to get past this? BIOS update?
THANKS!!

SIS-661 motherboard
Pentium 4, 3.80 (670)(LGA775) with hyperthreading
Windows XP Professional, SP2
2 Gigabytes Ram

 

[rolli59]

Try resetting the BIOS to defaults first, then update if does not work.

 

[Lethaltoast]

I had reset to defaults. I also removed battery to clear then replaced with new battery. Will try to upgrade BIOS. THANKS!