Dum Question about motherboards

My motherboards specs rate it as handling a P4 processor of 1.7 - 2.2 ghz.
Why?
If it's a 478 socket, won't use any 478 pin processor?
I've done some reading but I have not come across this yet.
Thanks!

 

The BIOS won't recognize anything more modern than the 2.2GHz. Occasionally a BIOS flash will enable higher speced procs to be used, but this is not always the case.

 

Ah, it's the bios. OK.
I want to upgrade the processor in my HP 512c from the stock 1.7 celeron, to the max specified, which states;
">= 2.2gHz Northwood".

(I know it's peanuts around here but it's the best I can do)

Intel's processor finder shows a very limited few that are; 1) 2.2gHz 2)400mHz in the 478 socket with .13 micron die, so I assume they will all work.
Anything else I should know that you can think of?
Thank you.

 

Make sure the northwood you get is Front-side bus 400 MHz and not 533 MHz.I believe this is the one you need.

http://www.ewiz.com/detail.php?name=P4_2.2-A

 

I sure will, guys. I'm grateful for your help.

 

I hope someone is still watching this thread because I need to know something else now that I have ordered the processor.
Will the fan on the 1.7 Celeron be OK for use on the P4?
The Intel site shows the P4 with lower thermal rating so I guess it actually runs cooler, but I wanted to make sure.

 

Hi ddp, No it is not boxed, I found a used pull from a reputable eBay seller and now, nervous type that I am, I am worrying about whether I need a different heatsink, or fan, or both, or whether what I have will work fine. There's much I do not understand and am probably making far too much of nothing.
From what searching I have done on the web it appears that my 1.7 celeron and the soon-to-be 2.2 P4 are similar enough that I can use the same heatsink but a new fan to replace the 4 year old OEM intel might be wise.
???