MP 1,1-5,1 MP 4,1 - Can I use only CPU 2 slot with dual CPU tray?

[orslow]

Recently, I broke some pins on CPU 1 slot while replacing CPUs, and after this, my mac just make hard fan noise when i boot it up, and show nothing ?

I think it is because of toasted CPU pins, so I tried just one CPU on CPU 2 slot, with nothing on CPU 1 slot, but it still does not work.

Can't I just use CPU 2 slot with dual CPU tray? or is there any other way to use only one CPU?

Thank you.

 

[tsialex]

Can't I just use CPU 2 slot with dual CPU tray?

No.

You can test a CPU tray with just one processor installed with CPU socket A. Don't work with just one processor installed with CPU B.

Btw, using only one CPU will make the SMC enter failure mode and fans will go full RPM/full time without any software rotation control. So, it's useful only for diagnostic purposes, no one can be near a Mac Pro running all the fans at max RPM for a long period of time.

or is there any other way to use only one CPU?

Unfortunately no, you will have to repair the CPU tray replacing the socket (expensive job and difficult to fins someone to do it) or buy a new CPU tray. You can buy a single CPU tray, btw.

 

[orslow]

No.

You can test a CPU tray with just one processor installed with CPU socket A. Don't work with just one processor installed with CPU B.

Btw, using only one CPU will make the SMC enter failure mode and fans will go full RPM/full time without any software rotation control. So, it's useful only for diagnostic purposes, no one can be near a Mac Pro running all the fans at max RPM for a long period of time.



Unfortunately no, you will have to repair the CPU tray replacing the socket (expensive job and difficult to fins someone to do it) or buy a new CPU tray. You can buy a single CPU tray, btw.

Thanks for your detailed reply.

Maybe I should buy single CPU tray as you recommended, and be careful when I replace CPUs next time ?

 

[tsialex]

Thanks for your detailed reply.

Maybe I should buy single CPU tray as you recommended, and be careful when I replace CPUs next time ?

The early-2009 backplanes and CPU trays have SMC firmware 1.39f5, while for mid-2010/mid-2012 the SMC version is 1.39f11. SMC is not updatable. If you have a SMC firmware version mismatch between the CPU tray and the backplane, the SMC will enter failure mode and the fans will go full RPM.

Sometimes you can find single CPU trays really cheap, the last early-2009 single CPU tray I bought for $75. Remember that you can't mix and match CPU trays and backplanes, if your backplane is a an early-2009, you need an early-2009 CPU tray.

Look at your local recycling center, maybe you can find one on the cheap, or even a bricked early-2009 Mac Pro with a working CPU tray that someone is selling cheap and you will have parts to sell to and make some money.

 

[orslow]

The early-2009 backplanes and CPU trays have SMC firmware 1.39f5, while for mid-2010/mid-2012 the SMC version is 1.39f11. SMC is not updatable. If you have a SMC firmware version mismatch between the CPU tray and the backplane, the SMC will enter failure mode and the fans will go full RPM.

Sometimes you can find single CPU trays really cheap, the last early-2009 single CPU tray I bought for $75. Remember that you can't mix and match CPU trays and backplanes, if your backplane is a an early-2009, you need an early-2009 CPU tray.

Look at your local recycling center, maybe you can find one on the cheap, or even a bricked early-2009 Mac Pro with a working CPU tray that someone is selling cheap and you will have parts to sell to and make some money.

Thank you again for reply.

If you didn't mention, maybe I could have bought mid-2010/mid-2012 ?

Maybe I should find online/offline used mac pro like you said. Actually, I also bought this mac pro on recycling center ?

Really appreciated for additional information that incompatibility between early-2009 and mid-2010/mid-2012.