Hello, I'm new to this forum.. English is not my first language so excuse me if I'm not clear enough.
I have a cmp 5.1 with a flashed GTX980
I was until now under Yosemite and never had any problem/trouble
Decided to move to Sierra yesterday, did the update to 10.12.5 from the App Store
Sierra loads with the EFI driver, no problem, I m under 10.12.5, the gtx is detected by the system
Then Nvidia propose the new web driver, I do the update for my new build, and... patatra...
I have a half startup, first everything looks fine, Apple Logo and status bar moving... and at half way... black screen :-/
The fans are running at full speed ! No image, black screen... but the computer is running, I can see it from the network and can access to the drives.
I disable the driver with the terminal in single user mode, reboot, computer run on the EFI driver like a charm, graphic card detected, so decide to try again, reinstall driver from nvidia website, go to terminal, enable nvidia web driver, reboot, and... black screen again.
Since then Im trying without success to find a solution to my problem :-/
Looking for people to help me to understand what's wrong since some people seems to have success with their update.
Thank you for your help.
Nicolas
EDIT 1: I disconnected my second monitor to test and computer now start ... So I plug it again, boom dual screen is working !!! I reboot to check and boom black screen again :-/ DVI output of the card.
EDIT 2 : Same symptoms with display port that I have tested.. Looks like I can only drive one monitor at the moment :-(
EDIT 3 : After unplug the power cord and plug it again everything seems to be normal 🙂 I dont know why and how but problems are solved..
Tks
Spec :
Mac Pro 5.1 2010 Dual 6cores @ 3,33Ghz
Flashed GTX980
32GB RAM @1333
Amfeltec Squid with 2x 512GB SM951 ahci raid 0
USB 3.0
BMD Mini Monitor 4K