Installing MacPro5,1 Processor Tray into MacPro4,1

Thanks for the info. I've also seen http://eshop.macsales.com/shop/turnkey/MacPro/2009_2010_Xeon_Processor/Apple_Mac _Pro_2009_2, but this is not what I'm planning to do. I do not wish to upgrade the 2 CPUs on my 4,1 processor board. I'm planning to completely replace it with a 1 CPU processor board of a MacPro5,1, replacing the complete tray.

I found an interesting post at http://forum.netkas.org/index.php/topic,852.660.html. Here is a quote:

"The ONLY difference between the 2009, 2010 and 2012 models of Mac Pro is the firmware version (4.1 in 2009, 5.1 in 2010 and 2012), the SMC fan-speed controller version (1.39f5 in 2009, 1.39f11 in 2010-2012), and a slight difference in CPU mounting. The latter two models use CPUs with integrated heatspreaders intact and a standard Intel-style CPU caddy. The 2009 model uses CPUs without heatspreaders.... So upgrading your firmware means that you really DO get a REAL 2010/2012 model out of your 2009 model. It's the same hardware. Although if you sell it 2nd hand you have to admit that it's an upgrade, because "About This Mac" reads the serial number and says Mac Pro 2009."

This suggest that it is possible to interchange the 5,1 and 4,1 Processor boards, provided the computers use the same firmware. That pretty much is what others are writing or copying and that's good enough for me right now.

Anyway, meanwhile I decided to get a quad-core Processor board for the MacPro4,1 from ebay for $120. If it doesn't work I can send it back. If it works, I'm going to look for a 3 GHz 6-core X56xx processor, which I should get for another $150. For me that's a better option and also a bit cheaper than upgrading the 8-core Processor board. The quad-core also supports CPU's up to 130 W, unlike the 8-core, which apparently seems to max out at 95 W.

I'm not going to contact OWC right now, because it's too much hassle.

Interesting. According to http://barefeats.com/hard183.html, which refers to a Mac Pro 2010, slots 3+4 share the same x4 uplink to the CPU too. There are several sources on the web outlining on a 4,1 and 5,1 Mac Pro, Slots 3 & 4 share the third channel. Do you still have the source of the information that this does not apply to the 5,1 model?

I have no plans to sell the system, ever. I once gave a IIvi away, and 10 years later I wish I didn't, but at least I still a IIci (my first Mac) with OS 6.0.8 for nostalgic reasons. It still works, even though some of the capacitors are probably dried out by now.

Faster RAM up to 1333 MHz max. is a matter of the CPU and firmware upgrade. Apparently, with the 5,1 firmware patch to support the 6-core CPU, the 4,1 processor board will also support 1333 ECC registered RAM up to 16 MB per module.

The system has an Apple Raid Card installed and 4 ES SAS drives 2 TB each and an Apple ATI HD5870. Except for the stupid battery in RAID controller, I'm very happy with it and the performance. I'm not planning to upgrade the RAM or storage system. My main intention for the upgrade is for fun and a CPU with AES support that will hopefully make file vault a bit faster and HDMI with audio if I put in video card with HDMI output. Currently I'm using a mini-DV to HDMI with USB sound adapter, but the converter gets very hot.

I found some information that states the SMC controller on the 5,1 is different than the 4,1. Apparently the SMC firmware update from MacPro4,1 to 5,1 uses 1.39f5 and is not the same as the firmware 1.39f11 on the original 5,1. I found one source that claims the fan's go crazy when mixing 4,1 and 5,1 Processor boards, but I have not been able to find a 2nd source to confirm this info. The problem could have been something else.

I think I can answer the question now. There was a misunderstanding regarding the firmware upgrade tool to upgarde a Mac Pro 4,1 to 5,1. The firmware upgarde tool does not update the SMC firmware, but installs a different boot rom version.

Mac Pro 4,1 (2009): MP41.0081.B07 (original)

Mac Pro 5,1 (2009): MP51.007F.B03 (upgraded)

The system and CPU board SMC version remains at 1.39f5 for the MacPro 2009. A Mac Pro 2010 uses 1.39f11. After upgrading a Mac Pro 4,1 to 5,1, the SMC firmware was still 1.39f5. SMC mainly deals with temperatures and fan speeds. It is important that the SMC version of the CPU and system are the same.

So to answer my question, it is not possible to use a 5,1 CPU board in a 4,1 system or vise versa. I'm not sure what happens when mixing them, but apparently the system does either not boot or the fan's go crazy, perhaps depending whether you put a 5,1 cpu board into a 4,1 system or vise versa.

Here are some links I found meanwhile for reference:

http://forum.netkas.org/index.php?topic=852.0;wap2

http://forum.netkas.org/index.php/topic,852.375.html

http://arstechnica.com/apple/2011/05/firmware-hack-can-transform-a-2009-mac-pro- into-a-12-core-monster/

Btw, the firmware upgrade tool 4,1 to 5,1 shows error 5570. That is because Apple changed the location of the 5,1 efi firmware image. You can however download the 5,1 firmware form Apple and simply mount the disk image prior to running the tool and it will work fine. Then shutdown the system and hold down the power button until a tone occurs, then the system will restart and show a progress bar to update the firmware.

As far as I know, the speed of your RAM depends on what your CPU and chipset supports. The 4,1 -> 5.1 upgrade allows to install a newer CPU Xeon 5600 series, that supports 1333 RAM. I suggest you type your CPU into Google to see what RAM speed it supports. Also when mixing different speeds of RAM, the lowest will rule. However, speaking of performance, you won't notice a difference between 1066 and 1333 RAM. I think the reason is latency vs frequency.