Dual Xeon W5590 no boot problem

[Fuzzb3k]

Hi. I recently bought two Xeon W5590 CPUs to upgrade my early-2009 Mac Pro, replacing the E5520 CPUs that were originally installed. When I swapped them out, the Mac Pro refused to boot - no startup chime, no video. I then tried a single W5590 in CPU socket A and it booted fine, so I tried the other one in there and that also booted fine. I then tried them both together again and ran into the same problem. Finally, I tried the original two E5520s just in case there was a problem with CPU socket B, but they also worked perfectly fine.

I know of other people who have done this same upgrade using the same CPUs, so it's not a case of the Mac Pro not supporting this model.

Has anyone had a dual CPU problem like this before? Seems strange that the CPUs work individually but not together.

There's some more info including pictures here: http://forums.macrumors.com/showthread.php?t=781908&page=11

 

[cmndr_andi]

Hi there,

It certainly sounds like your CPUs are OK and the board is physically OK. Could it possibly be a power issue? Since the E5520 is a 80W chip and the W5590 is a 130W chip.

That said I really know very little about how apple put together their mac pros - you would probably be best off posting this in the apple hardware section as it is packed with people using and upgrading these kind of systems.

 

[Fuzzb3k]

OK thanks for your input. I'm pretty sure it's not a power problem because I know of at least two other people who have done this very same upgrade without any issues, and the PSU & logic board are identical.

I've cross posted in the Apple forum: http://forums.overclockers.co.uk/showthread.php?p=18020312#post18020312

 

[mothermachine]

BIOS update required maybe? Never used a mc pro before so not sure if this is even possible/needed.