"No signal" with a Dell U2718Q HDR screen over HDMI

[shasoosh]

Hey all,

I'm having a really strange issue. I just got the above HDR screen and for some reason it won't connect to my Gigabyte GTX970 HDMI.

Things I've tried:

1. Connected my GTX970 to another screen over HDMI - Works
2. Connected a Mac Book Pro to the U2718Q over HDMI - Works
3. Connect my GTX970 to U2718Q over DP - Works
4. Booting with nv_disable=1 disables the drivers but still a black screen with HDMI
5. Changed resolution with SwitchResX to 1080p - HDMI works -> returned to 4k 60Hz -> No signal

The reason I need it over HDMI is due to the fact that HDR is supported only when connected with HDMI.

Is that a known issue?

Any help would be appreciated.

 

[wangbo223]

Hey all,

I'm having a really strange issue. I just got the above HDR screen and for some reason it won't connect to my Gigabyte GTX970 HDMI.

Things I've tried:

1. Connected my GTX970 to another screen over HDMI - Works
2. Connected a Mac Book Pro to the U2718Q over HDMI - Works
3. Connect my GTX970 to U2718Q over DP - Works
4. Booting with nv_disable=1 disables the drivers but still a black screen with HDMI
5. Changed resolution with SwitchResX to 1080p - HDMI works -> returned to 4k 60Hz -> No signal

The reason I need it over HDMI is due to the fact that HDR is supported only when connected with HDMI.

Is that a known issue?

Any help would be appreciated.

I have the same problem, did you get an answer?

 

[slim.jim]

I have the same problem, did you get an answer?

There is no native support in macOS for HDMI 2.0.

 

[shasoosh]

There is no native support in macOS for HDMI 2.0.

Thanks, figured it out eventually.

Any idea if Apple plans on supporting this in the future?

Has anyone tried this: mac-pixel-clock-patch-V2 ?

 

[TomHsiung]

What is it now? Natively 4K @60 Hz?