Use that link if your mobo is DEFINITELY a p4c800 deluxe and not a p4c800 or p4c800-e deluxe.
Your new cpu was supported from bios level 1017, so put the old cpu in,switch your machine on, and note the BIOS level reported on the POST screen.
If the number is lower than 1017, you need to upgrade the BIOS.
Ok got it. I was able to do it and flash the bios (big pain in the ass) but since I was running SCSI's and other ad ons I had to take it in so that they could redo the bios settings. I wish they would tell you this stuff on the website. Oh well I got it, and it's faster now. Thanks for your help everyone.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS