Another black screen on GTX-1080

[Gudd]

So, I've read a lot of posts about this but unless I'm wrong I don't think any specifically apply to my use case because of the system profilee i am using.

I have a Gigabyte GTX-1080. I'm using the new Nvidia web drivers quite happily but on boot my screen goes to sleep due to no signal about 1/3rd of the way through the Apple logo progress bar. The catch is that I'm not using a system definition that might be problematic (I'm using iMac 14,2) and my NVRam is functioning just fine as I have the Clover theme defined in there. If I switch input on my monitor and back again, MacOS detects the screen and everything wakes up.

For what it's worth, in System Profile my card just says "NVIDIA GeForce 1080 8191 MB", no mention of the brand. I don't care about that but it might indicate something is not quite right.

The card has 3 DP's and an HDMI, top to bottom on the left side, DVI on the right side. I can only get life out of the lowest DP, none of the others.

I've not updated my sig yet so: ASUS Gene VIII, i6700k, 32GB DDR4, GTX-1080, 2560x1080 monitor, various drives. Latest MacOS.

 

[P1LGRIM]

Have you tired AGDPfix.app ?
Link at the bottom of Post #1.

 

[Gudd]

I haven't, no. Reason being that I'm not using one of the affected MacPro6,1 or iMac15/17 system definitions.

However, that got me thinking that maybe (highly likely!) 2560x1080 is not a supported resolution for the internal screen of a 14,2 iMac. I wouldn't know as I've not owned an iMac since the first Core2Duo machines. I also wouldn't know if that would cause the lack of signal by itself.

So maybe I'll investigate the DSDT / SSDT method shown in your link when I get time and see if it gets me anywhere.