4,1 to 5,1 Mac Pro doesnt identify properly?

1. I think that machine was always a 5,1. But there should be a gray sticker near the PCI-e slots (outside) that has its factory specs on it.

I have a Mac Pro 2009 that was firmware updated to a 5,1 with the unsupported hack, and it shows SMC version 1.39f5, an older version.

Also, the 3.2 processor was never shipped in the 4,1 model, and if you went to the trouble of switching the processor, you would MUCH more likely switch to a hexacore.

2. If you ever decide to switch to a hexacore, you can use 1333MHz RAM DIMMs. So it is common among those who contemplate switching up to the hexacore (ever) to buy the faster 1333MHz DIMMs. They are around the same price. I have done this in my 2009 models Mac Pro as well. I always buy the faster DIMMs for my own computers, if they are near the same price and will work (at any speed).

They work fine in this machine in all varieties, but the Processor limits them to being seen as 1066MHz, not their true factory speed.

3. see 4 below first. You could re-apply the firmware update (and since yours is likely legitimate, you should be able to do that with Apple's procedure). But if it is working, I would not disturb it.

4. serial numbered Spare Parts are shipped to the stores and depots with no serial number. Apple has a serial-number re-installer program, and a procedure that is to be used when Installing a service part with no serial number. They do not allow it to non-Authorized repair center (but neither do they sell them non-serial-numberd spares). Your repair was not completed properly, since the replacement serial number was not Installed.

You should return it to the servicer, and ask them to finish the repair, or ask them to authorize a local Apple facility to install the correct new one (you will need a record of the repair for for this to work).

N.B.>> Without a serial number, you may not be able to Install any software updates. Apple cares deeply about Hackintosh (made from non-Apple parts) which it sees as theft of its MacOS.

Apple could have shut down the unauthorized firmware updates whenever they wanted, but they care MUCH more about Hackintosh.

I had the same problem (no serial no. reported in software) with my MacPro 2009 which I bought second hand, but it was originally a refurb. I can't remember if it was Mountain Lion or the subsequent OS, but I had problems signing into some iCloud services and at the time it was stated that the system serial number was required to validate some log-ins.

As a 60-mile round trip on public transport with a cheesegrater tower wasn't an attractive prospect, a search of the web led me to http://rogersm.net/icloud-problems-mountain-lion-serial-number and I got the utility and carefully followed the instructions. It worked for me, and System Information reports my serial number correctly, and my woes with iCloud log-ins vanished. I must stress this is totally unofficial and completely unsupported.

The gray label is shown on this nearby thread:

Re: "Model No.: A1289 EMC No.2314." is this 5,1 2010 Mac Pro?

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