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Downgrade Boot ROM?

C

cryptocat

macrumors newbie
Original poster
Sep 24, 2018
22
4
Quick question:


I'm on a 4,1=>5,1 - still running 10.11.6.

Boot ROM at MP51.0085.B00.
Reference 680 GTX flashed with Mac ROM.


If I install 10.14, will I be able to revert to an older Boot ROM Version? By running the official EFI restoration utility provided by apple or is it more tricky on a flashed (4,1=>5,1) machine?

I understand there's updated microcode, specifically protection against spectre/meltdown in the newer version, but I would rather not suffer the performance loss on this already-aging machine.

Might revert to 10.11.6 altogether, depending on graphic drivers. (Had a LOT of UI lag with 10.12/13 when I tried it with my 4K display.)

Thanks in advance from a long-time observer, who, after setting up his machine years ago, forgot most of the stuff he learned.
 
Forget about performance loss, anything that is lost with Spectre fixes will more than be compensated by the other improvements of 138.0.0.0.0.

If you want to install 10.14, you will have to upgrade to MP51.0089.B00 first with 10.13.6, then 138.0.0.0.0 when you open Mojave installer. Mojave don't let you install without upgrading your BootROM.

Even if you install Mojave then restore MP51.007F.03B from the Firmware Restoration CD, you will not boot your 10.14 install, since you need the APFS EFI module to access it.
 
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I know I won't be able to boot 10.14 with the old Boot ROM.

I just want to make sure I can downgrade everything just the way it was if any problems arise. My setup worked best on 10.11, 10.12/13 had horrible UI lag with the official nvidia drivers.

Thanks for laying out the upgrade-path again.

So firmware restoration should work just fine, regardless of 4,1=5,1 upgrade?
 
cryptocat said:
I know I won't be able to boot 10.14 with the old Boot ROM.

I just want to make sure I can downgrade everything just the way it was if any problems arise. My setup worked best on 10.11, 10.12/13 had horrible UI lag with the official nvidia drivers.

Thanks for laying out the upgrade-path again.

So firmware restoration should work just fine, regardless of 4,1=5,1 upgrade?
Click to expand...
Nope. The only way is doing a ROMDump/backup of your current BootROM with ROMTool.

Mac Pro firmware don't interfere with the NVIDIA drivers, you are worrying about the wrong thing. People that are forced to use 10.6.8 are upgrading to 138.0.0.0.0 just to have the PCIe 2.0 improvements and microcode corrections.
 
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If I am still on MP51.0085.B00, will I be able to upgrade to MP51.0089.B00 with my unflashed HD7950? Or do I need to dig around and find an EFI card before I can upgrade?
 
mrhansolo said:
If I am still on MP51.0085.B00, will I be able to upgrade to MP51.0089.B00 with my unflashed HD7950? Or do I need to dig around and find an EFI card before I can upgrade?
Click to expand...
You need a EFI card to upgrade to MP51.0089.B00. Only Mojave EfiUpdater2 can upgrade MP51.0089.B00 to 138.0.0.0.0 without a EFI GPU.
 
mrhansolo said:
If I am still on MP51.0085.B00, will I be able to upgrade to MP51.0089.B00 with my unflashed HD7950? Or do I need to dig around and find an EFI card before I can upgrade?
Click to expand...

You will need an EFI card to get to MP51.0089.B00

It is not yet 100% clear if Mojave firmware update will require MP51.0089.B00, or if it will work with previous versions. Beta shows it needs .0089 for many users.
 
bsbeamer said:
You will need an EFI card to get to MP51.0089.B00

It is not yet 100% clear if Mojave firmware update will require MP51.0089.B00, or if it will work with previous versions. Beta shows it needs .0089 for many users.
Click to expand...

Okay, but to upgrade from .0089 to 138.0.0.0.0 the 7950 without EFI will work though, correct?
 
Strangely enough, this is what the Mojave support page says...

Get macOS Mojave as an automatic download
macOS Mojave will download conveniently in the background on Mac computers running the latest version of OS X El Capitan or later. After it downloads, you’ll get a notification to install it.

If you don’t want macOS Mojave to download automatically, simply go to System Preferences, click App Store, then deselect “Download newly available updates in the background.”
Click to expand...

I'm not sure it's accurate, but that's what it says on their site... It could be that the cMP is an exception to this however. It may apply only to the models that don't need the same type of physical intervention for firmware upgrades.

https://support.apple.com/macos/mojave
 
crjackson2134 said:
Strangely enough, this is what the Mojave support page says...



I'm not sure it's accurate, but that's what it says on their site... It could be that the cMP is an exception to this however. It may apply to the models that don't need the same type of firmware upgrades.

https://support.apple.com/macos/mojave
Click to expand...
That won't work with Mac Pro, since you can't automatically upgrade the firmware. Just one more thing to disable…
 
Not an excuse, but Apple/support tends to think Mac (Pro) users are always keeping their machines up to date. Apple/support also know these machines are well past their tech support dates and contracts. Have a feeling they're in for a rude awakening from the non-technical when support starts getting calls or users start bringing these machines into stores for help.

Half of the genius bar tech folks at my local store have never first hand used a Mac Pro tower. Most probably haven't seen the trash can MP either since they stopped selling in-store in late 2014. I used to have a strong business relationship with that store's pro support contact, but they've abandoned those titles (at least locally) and that contact left the company for an independent firm. He would have been the best official help locally for those non-technical folks.

Unless they find this forum or others like it, people may just not update/upgrade or they'll run into major install issues. The installation of a "new" GPU does help that entry point barrier and hopefully those people ask for help first rather than cleaning up a messy issue.
 
Today was the first time I actually read that. I was looking for the posted release schedule for Mojave when I saw this. I just find it strange that they don't seem to know the limits of their own products sometimes. It's happened many times, but it always amazes me.

smh...
 
tsialex said:
Forget about performance loss, anything that is lost with Spectre fixes will more than be compensated by the other improvements of 138.0.0.0.0.

If you want to install 10.14, you will have to upgrade to MP51.0089.B00 first with 10.13.6, then 138.0.0.0.0 when you open Mojave installer. Mojave don't let you install without upgrading your BootROM.

Even if you install Mojave then restore MP51.007F.03B from the Firmware Restoration CD, you will not boot your 10.14 install, since you need the APFS EFI module to access it.
Click to expand...
i have a question about this tsialex

what if the boot partition is not APFS? could someone downgrade their bootrom after installing mojave?

i have noticed the "warm restart" issue is definitely a software problem. when i attempted to install lion via USB, all of the drives appeared fine in the disk utility. so it tells me either the OS or the bootrom are doing something that ****s up detection on warm restarts (cold boot, as you're aware, is fine)
 
broly said:
i have a question about this tsialex

what if the boot partition is not APFS? could someone downgrade their bootrom after installing mojave?
Click to expand...

Downgrades are not permitted since ThunderStrike. Apple efiflasher checks your current EFI firmware, only accept upgrades and reject any downgrades.
 
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tsialex said:
Downgrades are not permitted since ThunderStrike. Apple efiflasher checks your current EFI firmware, only accept upgrades and reject any downgrades.
Click to expand...

could you provide a decent set of links for someone who doesn't do this often?

essentially i want to flash the bootrom preceding the update for APFS>

i am hoping this will boot on mojave 10.14.6. it should, right?
 
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