Hey guys... I could find anywhere else more relevant than here to post this issue. Has anyone here experienced the indefinite black screen issue @startup for Mac Pro 5,1 Sierra 10.12.2 (latest update) and Nvidia GTX 980 with Nvidia's latest two web drivers? Simply an incompatibility issue? Or Need workarounds?
Mac Pro's GPU was on progress to be upgraded from MSI GTX 680 with boot screen (not sure flashed, how do I know if flashed?) to Nvidia GTX 980 reference design (unmodified) with the best hope of being able to boot into Sierra (albeit no boot screen). Even though I have managed to successfully install Nvidia's latest Web Drivers into Sierra, I can't seem to get past the indefinite black screen. Unusually, after power on, I hear apple chime twice and then nothing shows up on the screen.. I mean not even a blink or grey screen.. nothing at all - the monitor continues to say "no signal" and no "log in" screen shows up at all. I have tried to boot with the latest two web drivers which resulted in the same black screen with the same behavior of twice chime sound (PRAM reset itself?). And I switched back to GTX680 and it seems to be absolutely fine. Moreover the web drivers are checked as expected (not altered to OSX default drivers). However, GTX 980 with latest web drivers successfully works on El Capitan 10.11.6 (no boot screen). But I need it work on Sierra where my primary work applications reside. So simply say... GTX 980 is not compatible with Sierra in MP? If it is, would you have any suggestion for workarounds?
Here are more detailed info of what was involved in the process:–
System: Mac pro 5,1 2012 3.46Ghz Hex-core (cMP)
OS X: Sierra 10.12.2 (16C67), the latest update installed on Dec 15, 2016
Nvidia Web Drivers: (16C67) 367.15.10.25f01 or (16C67/68) 367.15.10.25f02 (lastest 1/6/2017)
Monitor: LG34UC88
Connection: HDMI or DP (used one at a time, displayed same black screen)
Hope this issue along with possible solution would help someone else out there!