Hi everyone,
I'm sorry to start a new thread here about that but can't find the one I followed... it was a 300+ pages one about installing windows on a Mac Pro 5,1. it's been months I haven't been here and every threads on this subject seem to be talking about open core (with is not the method I used)
Anyway here's my problem :
I've installed 3 different SSD's on a Mac Pro 4,1 flashed to 5,1.
On each, there's a different system : Mountain lion, Mojave, Windows 10 (in legacy mode)
I need to say that when I'm working on a system everything is fluid and flawless
BUT
I can't reach the boot screen when holding the option key at the startup
It "feels" like a windows problem...
1# If I hold the option key, after the chime, the fans go slightly up (around 20-25% speed) and black screen
2# If I select Windows from mountain lion startup disk selection, restart is done on Windows
3# if I select Mountain lion or Mojave from boot camp on windows, it restarts on Windows at a 80% frequency
4# If I reset the pram (3 chimes) and hold option key, fans go slightly up (around 20-25% speed) and a black screen
5# After a reset of the pram without the windows ssd connected, it starts on mountain lion. If I shutdown and start again while holding the option key, I get the boot screen selector once ! If I repeat this procedure, then black screen, fans up...
I've read about the sudo nvram manufacturing-enter-picker=true command... Do you think it will help me ?
Is there something else I need to check ? (I've installed windows by needs but I'm the worst noob ever on this os !)
Thanks in advance for your kindness
I'm sorry to start a new thread here about that but can't find the one I followed... it was a 300+ pages one about installing windows on a Mac Pro 5,1. it's been months I haven't been here and every threads on this subject seem to be talking about open core (with is not the method I used)
Anyway here's my problem :
I've installed 3 different SSD's on a Mac Pro 4,1 flashed to 5,1.
On each, there's a different system : Mountain lion, Mojave, Windows 10 (in legacy mode)
I need to say that when I'm working on a system everything is fluid and flawless
BUT
I can't reach the boot screen when holding the option key at the startup
It "feels" like a windows problem...
1# If I hold the option key, after the chime, the fans go slightly up (around 20-25% speed) and black screen
2# If I select Windows from mountain lion startup disk selection, restart is done on Windows
3# if I select Mountain lion or Mojave from boot camp on windows, it restarts on Windows at a 80% frequency
4# If I reset the pram (3 chimes) and hold option key, fans go slightly up (around 20-25% speed) and a black screen
5# After a reset of the pram without the windows ssd connected, it starts on mountain lion. If I shutdown and start again while holding the option key, I get the boot screen selector once ! If I repeat this procedure, then black screen, fans up...
I've read about the sudo nvram manufacturing-enter-picker=true command... Do you think it will help me ?
Is there something else I need to check ? (I've installed windows by needs but I'm the worst noob ever on this os !)
Thanks in advance for your kindness