I just got a new CPU, P4 2.4Ghz, 533Mhz, Socket 478. I installed it into my XFX P4XE-MVB Motherboard and can't get it to post. I contacted XFX via phone. They said the processor is fully compatible with the MB. The only thing i can think of is changing something in my BIOS.
Any help would be greatful.
PS my current BIOS is 06/13/2002-P4M266-8233-6A6LWP8HC-00

Thanks.
BlairJB

I dunno what to say man, they're right, it should work, the only thing i can think of is to reset the bios, or flash it (wouldnt reccomend flashing, but it could be the only option)try reseting the bios, you can find out how in the mobo's manual or online.

this probally wasnt much help, but that is a weird thing

Assuming the new cpu is properly and fully seated in it's socket, and any socket lever is locked........

If your bios version is new enough to recognize the cpu, it is detected automatically. The lists of supported cpus for your model on the mboard site either quote what cpus are supported if you have the newest or near newest bios version, or they list what minimum bios version you must have to support a particular cpu.
Obviously you can't change a bios setting if the mboard will not boot, and having a setting wrong beforehand will not affect whether the cpu is detected.
Your present bios version probably doesn't recognize the new cpu - on many computers, the computer will not boot if that's the case.
If you still have the old cpu, put it back in, flash the bios top the latest version, then install the new cpu. If you don't have it, take the computer to a PC repair place and they can do that for you.
......

On some more recent mboards you must have a three wire fan, normally the cpu fan, plugged into the cpu fan 3 pin header on the mboard - if no rpm is detected, the mboard will not boot, or it does boot but shuts down in a very short time.