northwood cpu

i just purchased an ibm motherboard that, as near as i can determine, can only take northwood cpus and not prescotts. i notice that northwoods come in 533 and 800 bus speed. i am not sure what my board handles since the board fru number was superseded and there is not a lot of info on the new fru number. do i have to worry about what speed northwood i get and will the 800 speed drop down to 533 if that is all the motherboard can handle. the original fru is 73P0596 and the superseded number is 89P7943. my research tells me the new number is used in the thinkcentre 8188 and came in 3.0 and 3.06 versions. the surplus vendor i went to said they has 2000 pieces and the first buyers were satisfied so for $30 i am taking a shot. thanks

I get similar results to you, like here:

http://www-306.ibm.com/pc/support/si...cid=MIGR-51316

where the 89P7943 (replacing 73P0596) is one of several boards specified for model series that use both 533 & 800 FSB Northwoods. Here it is specified as 533 FSB.

If the board is 533 MHz FSB and you get an 800 FSB CPU, it can't be said absolutely that it will operate, but if it does, it will be running at 2/3 of the speed, as the multiplier is locked.

i think i found that ibm page before and that is how i figured out the new fru number for the board. the description on the parts page says no agp but my board does have an agp socket so maybe that is how they cheapened it up a little for the new fru number. also, i noticed that the 3 cpu's that were used on the parts page for my new fru were the 2.8 and 3.06 both at 533 and a 3.0 at 800. i guess one of those is what i should shoot for. the guy that sold it to me said the bios needs to be updated but i think ibm has a feature where they do all the upgrades at one time. now i have to look for a cpu and get started on the board. thanks for the input