I have an XW9300 with a pair of Opteron single core 252's and the factory heatsink/fan assemblies.

I want to upgrade to a pair of Opteron 285 dual core CPUs.

Both the 252 and 285 CPUs are Socket 940 chips. It would be silly to buy the upgrades from HP: they're 300$ apiece! It's easy to find used Opteron 285's with identical stepping - not very expensive. I can't find any HP data on doing this upgrade, other than just buying the kits.

I would ASSUME that alll I need to do is swap out the single core chips, reinstall the heatsinks on the 285 chips, and I'd be good to go.

Anyone know different? I don't want to give up the machine as it has 8G of RAM,a high end video card and fast drives.

I've the same situation, what I did is taking out old Opteron 252 and replace 2 x Opteron 290 with good thermal pasted and old heat sink back
one thing you should concern is that thermal design for 252 about 92.5W mean while for Opteron 290 is 95W therefore you should expect
to see a HIGHER CPU TEMP at the idle. I believed most of AMD CPU is too HOT (that only thing make me don't like AMD design).
Anyway you should be OK though. (PS. use some SW to monitor your CPU Temp see what happen, mind is around 42-44 C at IDLE)
for 252 about 33-34 C at Idle you see that was a big different


Good Luck

Thanks for your note. I've been looking at Operon 285 CPU's. I think it's important that the 2 chips in the same XW9300 have the same stepping. But what about the different Operton Model numbers? I've seen both OSA285FAA6CR and OST265FAA6CB as being OK for use in XW9300. There are other model numbers as well for the Opteron 285. As long as they have identical stepping, does it matter whuich ones will work in the XW9300?