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EagleShogun

macrumors newbie
Original poster
Nov 30, 2021
5
2
Converted a 2012 Mac Pro Tower to Mojave and had it running with dependability when I shut it down. Later fired up the unit and the screen would not come up. Did the boot with external Mojave using bootable USB, holding option key while booting, shift key while booting, etc. No Avail! It sounds like the hard drive is operating trying to load but the monitor does not handshake with it. Changed monitors, changed graphic cards (both Metal types), ran graphic cards on another Mac Pro 2008, changed cables, double checked connections, etc. In sum, tried to verify everything was working separately on another machine which they seemed to be operating normally. The other machine was not converted to Mojave but was used to check various components.

I keep coming back to the monitor not connecting with the startup of the login. I think something went wrong on the files (that is where I am now) doing the login and activating the monitor.

That is kind of what the situation is in a nutshell. I do need suggestions including how to get into the problem without the monitor, probable causes, guidance, etc.

Equipment is Apple Mac Pro Tower 2012 with Nvidia GeForce 680, regular Mac Pro setup with extended memory 32 G, hard drives 2 gig active and 2 gig storage, converted to Mojave from El Capitan 10.11.6, followed instructions per Apple for conversion, etc. As said before, all the removable elements were tried twice on the machined after verifying the monitor, GeForce 680 board, cables and connections were working under another Mac Pro (2008) that has been operating under an other Metal type GeForce 680 enhanced graphic board. Everything seems to work when trying on the second Mac Pro but does not when used on the problem Mac Pro.

A little windy but I am trying to clear my mind of the problem and inform others for possible help.

Very interesting, Indeed! Nice to learn with new type problems which I have never come across prior to this one.

Any suggestions and opinions are very much appreciated.

Incidentally, I got involved in these Mac Pro conversions after following the website and threads for a while. I found them very enjoyable and I needed involvement in a major problem such as this to keep me occupied after recently turning 80 and felt likeI was being led out to pasture. I love this problem because it keeps me involved and learning.

Hopefully, everyone understands where I am coming from on the background.
 

Bodhitree

macrumors 68000
Apr 5, 2021
1,944
2,048
Netherlands
Congratulations on your 80th and still being that involved with tech! My stepfather is 85 and has forgotten what the icons on the Home Screen of his iPad all do. He just about remembers how to turn on the web browser and fire up YouTube.
 

joevt

Contributor
Jun 21, 2012
6,689
4,086
What kind of GeForce 680? Is it a PC graphics card? Was it flashed with a Mac firmware? Or is it a EVGA Mac Edition?
What monitors?
What connection types did you try? VGA, DVI, HDMI, or DisplayPort?
 

KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
592
converted to Mojave from El Capitan 10.11.6,
If you never installed an OS newer than El Capitan, for upgrading to Mojave natively, you have to install High Sierra first.
This has to do with BootROM updates that come with certain OS installers like High Sierra and Mojave.
If you jumped from El Capitan, I suppose you did a patched install e.g. Dosdude Patcher.

I would recommend to reinstall El Capitan and go from there i.e El Capitan> High Sierra > Mojave.
Note that there's a forum dedicated to Mac Pro , might be interesting and you may get more help there:

There's an excellent thread about how to install Mojave natively (which has a few advantages) .
Post #1 is a bit extensive , but covers all possible scenarios :
 
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KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
592
Did the boot with external Mojave using bootable USB, holding option key while booting, shift key while booting, etc. No Avail!
This is a known bug when there's a Kepler nVidia card (like the GTX 680) installed:
The installer will not work when it's on a USB .
So there are 2 possibilities: install another drive in one of the internal bays for the installer or upgrade EC> HS > Mojave on the internal drive itself.
 

EagleShogun

macrumors newbie
Original poster
Nov 30, 2021
5
2
You Guys/Gals are good. I back doored the problem to somehow possibly loosing the EFI, possible damage to the bootRom process, and similar related items. All parts used on the machine have been tested and they work on another Mac Pro (2008). I am centered on how and why the screen and the bootRom may not be talking to each other. Then there is firmware. The Nvidia GeForce 680 card in machine is one made for Apple Mac Pro; I do have another one that is a flashed unit. I think I will have to go to Apple Repair business to have another hard drive setup with all the proper elements that I need (EFI, firmware, etc) for the High Sierra 10.13.6.

The 2008 Mac Pro has El Capitan 10.11.6 installed. Can I update that software and connect it to the Mac Pro I am trying to convert eventually to High Sierra and then to Mojave? This way I could use the existing 5,1 hard disc and have the other machine control formatting and downloading, etc. Could be making it dirty than what I have already done.

Just thoughts and ramblings - need to get a new 5,l hard drive to make any changes I need and save.

The references, suggestions, opinions, answers, etc are taken very seriously in providing answer(s) to my situation. This I thank you.
 

KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
592
You're welcome, glad to be of some help!

Then there is firmware. The Nvidia GeForce 680 card in machine is one made for Apple Mac Pro; I do have another one that is a flashed unit
The GTX 680 works in the MP regardless having a Mac EFI or just a PC version, so that's no problem.
I think I will have to go to Apple Repair business to have another hard drive setup with all the proper elements that I need (EFI, firmware, etc) for the High Sierra 10.13.6.
Personally I wouldnt do that. The MP is obsolete for Apple and this may cost an amount probably without the desired effect.
I'm quite sure that you (with the help of people here) will solve this puzzle : )
The 2008 Mac Pro has El Capitan 10.11.6 installed. Can I update that software and connect it to the Mac Pro I am trying to convert eventually to High Sierra and then to Mojave? This way I could use the existing 5,1 hard disc and have the other machine control formatting and downloading, etc. Could be making it dirty than what I have already done.
Generally I wouldnt recommend to install an OS on a (different) Mac and swap the drive to another Mac device.
That said, you could:
- make a bootable El Capitan USB installer on the MP 2008
- boot the MP 5,1 from the EC USB installer, open Disk Utility (in the menu bar) and format the internal drive to GUID partition and HFS+(Mac OS journaled).
- install EC to the internal drive of the MP 5,1

If all works out as it should, you have a running MP 5,1 and you can download HS installer (on the internal drive) and upgrade to High Sierra.
Once done , repeat the same process to get Mojave installed .

EDIT: I just saw that you replied to this topic in the thread I recommended (Mojave) .
At least that's how I understand ...
If so, perhaps it's better to delete (or copy here) that reply to avoid confusion and /or cross-posting...
 
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EagleShogun

macrumors newbie
Original poster
Nov 30, 2021
5
2
Did not realize I was cross posting in duplication. Will stay with one thread. Update will be posted on Theo thread here and the other eliminated. The graphics board moved from a possible to a probable cause. Board did not work on the 2008 Mac Pro. Will continue to look for other possibilities because I want to understand as much of the Mac Pro 2012 as possible. Will return to the original starting point and proceed from that point. Suspect there other problems lurking.
 

KeesMacPro

macrumors 65816
Nov 7, 2019
1,453
592
Did not realize I was cross posting in duplication. Will stay with one thread. Update will be posted on Theo thread here and the other eliminated. The graphics board moved from a possible to a probable cause. Board did not work on the 2008 Mac Pro. Will continue to look for other possibilities because I want to understand as much of the Mac Pro 2012 as possible. Will return to the original starting point and proceed from that point. Suspect there other problems lurking.
This is a link for the Technician Guide Mac Pro 2010 (identical to the 2012) to download.
There's a lot of info there, could be interesting for maintenance and it contains lots of helpful methods for troubleshooting.
 
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EagleShogun

macrumors newbie
Original poster
Nov 30, 2021
5
2
Got it and copied/printed out - 226 or there about pages. Just what I needed; thank you. Does anyone know where one can get a Nvidia GeForce GeForce 680 board can be checked/repaired in case I determine the graphic board is the problem. I need to explore all avenues including sources of repair; at the price paid not ready to admit it could be a throwaway. It is originally a graphic board for Apple which includes Metal.

The information source just obtained should give me a better understanding what the different computer items do and how they a attached including functions and operations scope. I love problem solving.
 
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