Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

tsialex

Contributor
Jun 13, 2016
13,459
13,608
Turns out this 2009 is running a B08 firmware, but it has a ton of issues, it can't accept any ram over 2gb, takes forever to boot, and just is running kinda wacky. How can I downgrade to B07 and then flash to 5,1?
Apple removed the possibility of downgrading firmwares more than a decade ago. You can't do it, no Apple tool permits it.
You can always pay a firmware engineer to reconstruct a new SPI flash image based on a dump of your current BootROM, but this involves cost and don't make any sense to do for a defective/problematic backplane.
 

GreppMichaels

macrumors member
Apr 17, 2020
67
13
Los Angeles, CA
Apple removed the possibility of downgrading firmwares more than a decade ago. You can't do it, no Apple tool permits it.
You can always pay a firmware engineer to reconstruct a new SPI flash image based on a dump of your current BootROM, but this involves cost and don't make any sense to do for a defective/problematic backplane.

Ok, I'm honestly not sure if my RAM and boot issues are related to the backpane, just speculating. I've seen you help another user with a B08 Bootrom, I just need to update my 4,1 with that bootrom to a 5,1. Is that possible?
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
Ok, I'm honestly not sure if my RAM and boot issues are related to the backpane, just speculating. I've seen you help another user with a B08 Bootrom, I just need to update my 4,1 with that bootrom to a 5,1. Is that possible?
Like I said on my previous post, it's not possible anymore and the only workaround is via a firmware reconstruction. Even back in the day it was really really difficult to cross-flash a MP4,1 that came from Apple with B08 BootROM, now it's just impossible with the old tools.

Again, don't make any sense to invest money and time to reconstruct the firmware of a problematic backplane. If you have any hardware problems with your backplane, just forget it.
 

GreppMichaels

macrumors member
Apr 17, 2020
67
13
Los Angeles, CA
Like I said on my previous post, it's not possible anymore and the only workaround is via a firmware reconstruction. Even back in the day it was really really difficult to cross-flash a MP4,1 that came from Apple with B08 BootROM, now it's just impossible with the old tools.

Again, don't make any sense to invest money and time to reconstruct the firmware of a problematic backplane. If you have any hardware problems with your backplane, just forget it.

Ok cool, I appreciate you very much my dude, you've always been incredibly helpful and patient. So I'm to assume my inability to boot anything more than 2gb of ram across one or two sticks, along with the insanely long boot times in general, are directly related to my backpane, given I get the same results regardless of my CPU tray. And given I can't update the bootrom anyway, or it's extremely cost prohibitive, I'm better off just replacing the back pane regardless?
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
Ok cool, I appreciate you very much my dude, you've always been incredibly helpful and patient. So I'm to assume my inability to boot anything more than 2gb of ram across one or two sticks, along with the insanely long boot times in general, are directly related to my backpane, given I get the same results regardless of my CPU tray. And given I can't update the bootrom anyway, or it's extremely cost prohibitive, I'm better off just replacing the back pane regardless?
A lot of people with B03/B07 (or even mid-2010/mid-2012 with the original firmware) get in contact with me and ask for help just to not have to spend so much time with the convoluted cross-flash and upgrade process, it's just that for a problematic backplane, it's not worth to spend around 1/3 of the price of an used one on eBay for a firmware reconstruction.
 
Last edited:

Technewszone.com

macrumors newbie
Oct 31, 2020
2
0
Nevada
Firmware upgrades are not possible with hacked/patched macOS installs. You will never upgrade your firmware with a hacked system. Start with a complete vanilla install of El Capitan or Sierra.

First cross-flash your 2009 Mac Pro to MP5,1 firmware using netkas forum cross-flash method, after that upgrade to Mojave using the instructions of the first post of this thread:

I saw that you mentioned a way to get a reconstruction of the firmware to upgrade a Mac Pro with MP41.0081.B08 to 5,1..How does that work, can you send me the link?
I tried the other methods and they do not work. How does the reconstruction of the firmware work?
 

MagicMacMike

macrumors newbie
Nov 22, 2020
2
0
BootROM reconstruction is a very different process than a cross-flash with the MacEFIROM tool, where you just upgrade the EFI part of the BootROM and everything else inside the image is kept MacPro4,1. An early-2009 Mac Pro cross flashed by the Netkas forum method, what we call an MP4,1>5,1 hybrid, have just the MP5,1 EFI and all other components of the BootROM firmware image (the NVRAM/BootBlock/hardwareIDs) are still MP4,1 versions, this cause several problems like the impossibility of using Firmware Restore CDs and makes an MP4,1>5,1 hybrid much more susceptible to bricking.

SMC: The 1.39f5 SMC firmware version is independent of the BootROM and immutable, it's not possible to use a mid-2010/mid-2012 CPU tray with an early-2009 Mac Pro backplane, or vice-versa. When the SMC firmware version is mismatched, the SMC micro controllers will enter fail-safe mode and will run all the Mac Pro fans at the fastest RPM, all the time. It's like being on the side of a jet turbine.

Nehalem vs Westmere Xeons: Apple supported dual CPU Nehalem Xeons officially up to El Capitan. While up to High Sierra, the dual CPU Mac Pros that still have Nehalem Xeons work perfectly, Mojave don't support dual CPU Mac Pros that still have the original Nehalem processors anymore. A dual CPU Mac Pro that still have the Nehalem Xeons will KP when waking from sleep and the audio will have maddening stuttering problems when running Mojave and newer macOS releases, the only way to solve this is upgrading the Nehalem processors to Westmere. Only MP5,1 firmwares support Westmere Xeons, MP4,1 firmwares don't support it, the firmware reconstruction, or the cross flash to MP5,1, is a requirement to run Westmere Xeons. Single CPU Mac Pros don't have the waking from sleep and the audio stuttering problems, just the dual CPU ones that still have Nehalem Xeons.

BootROM Reconstruction: Reconstruction is a service, you dump the SPI flash memory with ROMTool or flashrom, take pictures of the ESN and the MLB labels, send me and I'll reconstruct a new BootROM image tailored specifically for your Mac Pro, based on the generic 144.0.0.0.0 upgrade image, with the MP5,1 firmware standard (MP5,1 EFI/NVRAM/BootBlock/hardwareIDs).

After the reconstruction, your Mac Pro will be identified as a MacPro5,1 and be able to run Mojave officially/natively if you have a METAL supported GPU. While an early-2009 Mac Pro flashed with a reconstructed BootROM image will have the same BootROM firmware specification of a mid-2010 Mac Pro, the serial number is kept the same and when AboutThisMac validate the serial remotely with Apple it will display that you have an early-2009 Mac Pro, this is cosmetic only, software support will be the same as a real mid-2010/mid-2012 Mac Pro.

I've sent you a PM with detailed instructions, if you are interested.


@tsialex - I just purchased a dual CPU 4,1 with MP41.0081.B08 boot ROM.

After reading your responses extensively I am assuming that the conventional MacPro2009--> 2010 firmware tool will not work with this machine due to the MP41.0081.B08. I have various GPU's as well as Westmere and Nehalem processors on hand if necessary to swap out parts and perform a flash upgrade myself.

Am I correct to assume that the only option to safely turn a 4,1 running MP41.0081.B08 into a 5,1 is to perform a BootROM Reconstruction ? If so would you please contact me with instructions/pricing or any other relevant information?

Thank You!
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
@tsialex - I just purchased a dual CPU 4,1 with MP41.0081.B08 boot ROM.

After reading your responses extensively I am assuming that the conventional MacPro2009--> 2010 firmware tool will not work with this machine due to the MP41.0081.B08. I have various GPU's as well as Westmere and Nehalem processors on hand if necessary to swap out parts and perform a flash upgrade myself.

Am I correct to assume that the only option to safely turn a 4,1 running MP41.0081.B08 into a 5,1 is to perform a BootROM Reconstruction ?
Correct.
If so would you please contact me with instructions/pricing or any other relevant information?

Thank You!
Sure, I'll send you a PM with instructions early tomorrow morning.
 
  • Like
Reactions: MagicMacMike

USmacs

macrumors newbie
Dec 30, 2013
11
4
I just spent the last two days screwing with a 2009 with B08 boot rom and reading through here and Netkas. I successfully updated it to 5,1 using El Capitan 11.6. Tsialex saying it was not possible really threw me, (As he seems to know everything! #Respect.) but by searching every one of the 82 pages for B08 I found a bunch of people with B08 that said they had sucessfully updated http://forum.netkas.org/index.php/topic,852.0.html

I still screwed around a bit in El Capitan but I think as I had tried to use the terminal work around and had renamed my EFI update files, that may have been the issue in 11.6. I just downloaded the 1.5 firmware from Apple again and then it worked.

B08 is not a life sentence!

PS.
I installed El Cap on a rotational HD for the hell of it (never had an issue with a SSD before and I've done this many many times). PRAM reset and then boot to recovery to disable SIP. Machine only has a GT120 and the HD installed.
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
I just spent the last two days screwing with a 2009 with B08 boot rom and reading through here and Netkas. I successfully updated it to 5,1 using El Capitan 11.6. Tsialex saying it was not possible really threw me, (As he seems to know everything! #Respect.) but by searching every one of the 82 pages for B08 I found a bunch of people with B08 that said they had sucessfully updated http://forum.netkas.org/index.php/topic,852.0.html

I still screwed around a bit in El Capitan but I think as I had tried to use the terminal work around and had renamed my EFI update files, that may have been the issue in 11.6. I just downloaded the 1.5 firmware from Apple again and then it worked.

B08 is not a life sentence!

PS.
I installed El Cap on a rotational HD for the hell of it (never had an issue with a SSD before and I've done this many many times). PRAM reset and then boot to recovery to disable SIP. Machine only has a GT120 and the HD installed.
The problem is to do successfully all the steps required - while some people can do it all, most can't even find the correct DMGs needed.

Another thing, cross-flashing is deprecated since your Mac Pro BootROM image now is a hybrid of MP4,1 and MP5,1 BootROMs, some components of the BootROM image are updated, others hacked to work and some are still MP4,1:
  • MP5,1 EFI - replaced the MP4,1 EFI.
  • MP4,1 NVRAM volume - as is, not changed and this is a real problem.
  • MP5,1 EFI BIOS/CSM - replaced the MP4,1 EFI BIOS/CSM.
  • MP5,1 BootBlock - MacEFIROM tool replaces it with the 1st MP5,1 BootBlock version extracted from the first MP5,1 firmware update, know to have several problems with PCIe switched cards and that Apple constantly iterated when HighSierra and Mojave firmwares were released, but this can't be updated with Apple efiflasher tools for final users, only a reconstruction.
  • MP4,1 Bootloader hacked to work with MP5,1 EFI.
 

USmacs

macrumors newbie
Dec 30, 2013
11
4
I tried Sierra (That I've normally used a couple hundred times already), Yosemite (someone said 10.10 worked for them) and then El Cap. It's possible that I could have got it to work in Yosemite as I had already replaced and renamed the DMG EFI files and only dl'd a new EFI file in El Cap, but it definitely would not work in Sierra.
The terminal work around was a PIA and I could not get it to work even when I fixed the errors in the provided code.
 

pointvicente

macrumors newbie
Sep 18, 2014
29
1
Moral of the story DO NOT PROCEED with flashing a 4,1 to 5,1 if you have the B08 firmware. As tsialex mentioned above you will have several issues and there are no clear workarounds documented. Unless you are able to perform a ROM dump and pay a professional for a reconstruction of your Bootrom, then avoid Mac Pro's with the B08 firmware.
 
  • Like
Reactions: Macschrauber

pointvicente

macrumors newbie
Sep 18, 2014
29
1
Moral of the story DO NOT PROCEED with flashing a 4,1 to 5,1 if you have the B08 firmware. As tsialex mentioned above you will have several issues and there are no clear workarounds documented. Unless you are able to perform a ROM dump and pay a professional for a reconstruction of your Bootrom, then avoid Mac Pro's with the B08 firmware.
FYI i used the netkas bootrom tool and finally upgraded the B08 without any issues so far. Now i am using mojave and opencore/windows 10 no issues.
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
FYI i used the netkas bootrom tool and finally upgraded the B08 without any issues so far. Now i am using mojave and opencore/windows 10 no issues.
The problems with the MP4,1 NVRAM differences to the MP5,1 one happen over time. It's not if will happen, it's when it will happen.
 

pointvicente

macrumors newbie
Sep 18, 2014
29
1
which is why i did a bootrom dump before hand. but heck everyone is dumping the cheese grader for peanuts so why not buy another one if problems do occur.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.