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116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
Hello:
I work at a school where we have a computer lab with 7 similar mac 4,1 flashed for 5,1. 16g ram 4-core intel xeon and nvidia gt 120.
I have updated them to monterey (from high sierra) using the oclp.
With six of them all went smoothly. With the last one, however, it got stuck for hours during installation. I rebooted and let the process continue but got stuck again.
I then rebooted and tried to reinstall from scratch but got also stuck. All I got was an apple logo screen frozen for hours.
After that, anything I tried (booting from another drive, from an usb, etc.) got stuck in the apple logo.
I tried to reset vram, but it only chimed twice. And now when I power up it just chimes but turns off in 10-15 seconds after that.
I have read this post https://forums.macrumors.com/threads/mac-pro-2009-boots-chimes-then-shuts-off.2333216/
thoroughly but I cannot find out what to do.
Please, any help will be much appreciated since we need the computer and we are very short of budget.
Thanks a lot
 
Last edited:

Macschrauber

macrumors 68030
Dec 27, 2015
2,948
1,472
Germany
remove the BR2032 battery and try to boot.

Also check the voltage, below 3.0 Volts it should be replaced, if it's well under 3.0 Volts it could be the culprit.
 

116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
remove the BR2032 battery and try to boot.

Also check the voltage, below 3.0 Volts it should be replaced, if it's well under 3.0 Volts it could be the culprit.
Thanks for the hint.
It didn't work though. Same thing again: it chimes, and then it shuts down after 15-20 seconds.
The screen is black all time.
 

tsialex

Contributor
Jun 13, 2016
13,399
13,552
If you reset the SMC, remove the RTC battery and you still can't boot a working supported macOS drive, then you have a brick. You gonna need a replacement SPI.

I'd try again, to be absolutely sure, with a confirmed working AppleOEM GPU from another Mac Pro, see if you get at least the grey screen on the display.
 

116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
O
If you reset the SMC, remove the RTC battery and you still can't boot a working supported macOS drive, then you have a brick. You gonna need a replacement SPI.

I'd try again, to be absolutely sure, with a confirmed working AppleOEM GPU from another Mac Pro, see if you get at least the grey screen on the display.
Oh man... This sounds awful!
Just some questions:
How do I reset the SMC?
What is an SPI? And more important... HOw much does it cost??
Thank you very much for your help
 

tsialex

Contributor
Jun 13, 2016
13,399
13,552
How do I reset the SMC?

Remove the power cable from the PSU for at least 20s.

What is an SPI?

SPI flash memory, where the Mac Pro BootROM is stored.

And more important... HOw much does it cost??

If you can replace a SOIC-8 SMD chip, you can replace it for around $20 (MX25L3206E + flux + braid), less if you just need the flash memory, but since you didn't even knew what a SPI is, seems that is not something easier for you and you won't have a SPI flash programmer, hot air station and etc.

If you can't do it yourself, a MATT card will cost you €65 from cmizapper.com, but this will just get you booting again, you'll still need to repair the Mac Pro own BootROM.

Maybe a 2nd hand replacement backplane will be easier/cheaper for you.
 

116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
Remove the power cable from the PSU for at least 20s.

I tried, but it didn't work either. :(

You are right; my knowledge about computer hardware is very limited. I guess I will have to get it repaired by the tech service :(

I really appreciate your help. Just one last question: how is it possible to brick a computer when updating the SO? I never thought it could be such a critical operation. What baffles me more is that I did the same update on another six computers with exactly the same specs and everything went smoothly!

In any case, thanks a lot once more.
 

tsialex

Contributor
Jun 13, 2016
13,399
13,552
Just one last question: how is it possible to brick a computer when updating the SO? I never thought it could be such a critical operation. What baffles me more is that I did the same update on another six computers with exactly the same specs and everything went smoothly!

When things are over pressure, they break.

Think about it, you/someone else cross-flashed a Mac Pro from early-2009 (so, at least 14 years old) that was designed to work with Leopard to El Capitan, then you used OCLP to install Monterey - the early-2009 BootROM was not designed for that type of usage. The NVRAM of a MacPro4,1 is not resilient enough to work over high pressure - differently from modern Intel Macs that have the T2 to manage it.

MacPro5,1 NVRAM volume is a little better designed than a MacPro4,1, but it's a product from a past era, when NVRAM usage was eventual and not constant like is nowadays.

The best example of NVRAM pressure is what happens like when you install an unsupported macOS release that have SSV, just the staging of the NVRAM entries required for the install is enough to brick a NVRAM volume that is not in good shape.
 

116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
Remove the power cable from the PSU for at least 20s.



SPI flash memory, where the Mac Pro BootROM is stored.



If you can replace a SOIC-8 SMD chip, you can replace it for around $20 (MX25L3206E + flux + braid), less if you just need the flash memory, but since you didn't even knew what a SPI is, seems that is not something easier for you and you won't have a SPI flash programmer, hot air station and etc.

If you can't do it yourself, a MATT card will cost you €65 from cmizapper.com, but this will just get you booting again, you'll still need to repair the Mac Pro own BootROM.

Maybe a 2nd hand replacement backplane will be easier/cheaper for you.

If you reset the SMC, remove the RTC battery and you still can't boot a working supported macOS drive, then you have a brick. You gonna need a replacement SPI.

I'd try again, to be absolutely sure, with a confirmed working AppleOEM GPU from another Mac Pro, see if you get at least the grey screen on the display.

Hi again:
Good news!
I replaced the GPU and using an HD with a supported OS the computer booted. Which is great.
Now, here comes my question: is there anything I can do to fix the issue now that I can boot it? I would need to upgrade the OS since most of the apps have ceased working.
Thanks a lot
 

tsialex

Contributor
Jun 13, 2016
13,399
13,552
Now you need to repair the BootROM, I’ll send info about the BootROM reconstruction service by PM (top right of the page, white letter icon).
 

116iniesta

macrumors newbie
Original poster
Jan 19, 2024
19
1
Now you need to repair the BootROM, I’ll send info about the BootROM reconstruction service by PM (top right of the page, white letter icon).
Oh, thanks a lot. That is really kind.
Thank you so much.
 
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