MP 1,1-5,1 Mac Pro 5,1 2010 does not boot after installing Mojave, GPU GTX 680

[Batezoid]

I recently installed EVGA GTX 680 2GB flashed to Mac GPU into Mac Pro 5,1 2010 to upgrade to Mojave. Also due to the original Radeon HD 5770 was failing, and the machine kept reverting back to the login screen. The GTX 680 was working fine in High Sierra, perfectly stable, all ports working etc. Upon installing Mojave, halfway into the installation the screen went black/no signal. upon rebooting the task bar reaches half way then again the screen goes black/no signal.

After much trial and error the machine boots and works with a GT 120 card! So I know the Mojave installation was successful and the firmware is 144.0.0.0.0. The GTX 680 just doesn't work

I have tried the same GTX 680 in a different machine and it works perfectly, so I am very confused. The only thing that was different was the monitors.

The machine in question is at my work place, so any help and advice would be much appreciated. Browsing this forum and the Internet in general it appears to be a common problem but I haven found a solution.

 

[Macschrauber]

Is that a native installation or is a kind of a patcher involved?

does not need any Patch for a 144 Firmware Mac Pro.

only issue is: createinstallmedia stick would not install with a Kepler gpu. Boot from High Sierra and use the Installer App instead.

 

[Batezoid]

Thanks. Native installation. I installed a clean HD with High Sierra then updated to Mojave in the app. The same result. I’m at a loss.

 

[Macschrauber]

only issue I can think of is: do you use an ancient vga Monitor. After the driver loads vga is no longer supported.

 

[joevt]

What display are you using? What GPU connector? I use dual link DVI-D on my GTX 680. DisplayPort might not work.

 

[Batezoid]

It’s strange, the monitors were working with High Sierra. I’ve tried an HDMI monitor, DVI to VGA etc. I’ve also tried another GTX 680, it does the same thing.

is it possible to reset the firmware and start over?

 

[MarkC426]

Did you buy the gpu flashed, or do it yourself?
Maybe a bad flashing.

I can't see your old gpu causing mac to go back to login screen, there is something else wrong there.

 

[joevt]

It’s strange, the monitors were working with High Sierra. I’ve tried an HDMI monitor, DVI to VGA etc. I’ve also tried another GTX 680, it does the same thing.

is it possible to reset the firmware and start over?

does etc mean you tried DVI-D? VGA from DVI-I is separate from DVI. You could try a DVI-D to HDMI adapter.

 

[Batezoid]

Did you buy the gpu flashed, or do it yourself?
Maybe a bad flashing.

I can't see your old gpu causing mac to go back to login screen, there is something else wrong there.

Thanks. I didn’t flash this one, but it works in another machine. I also tried a working card I flashed myself, this does the same thing.

I am wondering if the firmware update didn’t work properly?

 

[Batezoid]

does etc mean you tried DVI-D? VGA from DVI-I is separate from DVI. You could try a DVI-D to HDMI adapter.

Thanks. I have tried HDMI to HDMI , DVI-D with HDMI adapter to HDMI, DVI-I with VGA adapter to VGA. They are monitor that are used more for CCTV

I might bring to work a monitor from home that I know works with the card.