[SOLVED] G-Sync compatible: HDMI and/or HDR

[kaipirinha]

Wanting G-Sync severely limits the choice for a new Monitor so I am thinking about a G-Sync compatible one, like the acer predator cg7 cg437kp. This example Monitor is G-Sync compatible and generally supports “adaptive sync” from 48 to 60Hz on HDMI Inputs and 48 to 120Hz on DP Inputs.
But I read that G-sync only works with Display Port. So, I would not be able to use it over HDMI? I would be able to live with that but it raises a much more important question: I also read that (only?) G-Sync Ultimate supports HDR. Does this mean HDR and G-Sync compatible mode are not useable at the same time? Having both HDR and G-Sync is one of the main reasons for me to consider this (very expensive) Monitor.
Edit: To clarify, I would connect the Monitor via Display Port, HDMI just got me to the question of limitations.

 

[sizzling]

You don’t need G-Sync ultimate for HDR and G-Sync, I have both on a certified monitor. However to gain an ultimate rating it used to be a monitor needed to achieve 1000 nit brightness but recently NVIDIA have modified the standard and it’s not as clear what a monitor requires to pass.

What I do find strange is that monitors do not support G-Sync via HDMI yet the 2019 & 2020 LG OLED TV’s support G-Sync over HDMI so it’s clearly possible.

 

[Glenwing]

There are four different variable refresh rate protocols:

• Original NVIDIA G-Sync protocol —Proprietary protocol for DisplayPort, only supported by NVIDIA. Developed by NVIDIA in 2013 before a standardized protocol existed. G-Sync module monitors use this protocol, so AMD cards can't use variable refresh rate on those monitors.
  
  
• VESA Adaptive-Sync — Part of the DisplayPort standard, supported by both AMD and NVIDIA (1000 series and above only).
  
  
• AMD FreeSync over HDMI — Proprietary protocol for HDMI, only supported by AMD. Developed by AMD in 2015 before a standardized protocol existed. Most monitors still use this protocol to support variable refresh on HDMI, so NVIDIA cards can't use variable refresh over HDMI on those monitors.
  
  
• HDMI Game Mode VRR — Part of the HDMI Specification, supported by NVIDIA (1600 series and above only). AMD promised support with driver update, still waiting.

Support for variable refresh rate will vary based on your graphics card and which protocols are supported by the display.

 

[Glenwing]

There are four different variable refresh rate protocols:

• Original NVIDIA G-Sync protocol —Proprietary protocol for DisplayPort, only supported by NVIDIA. Developed by NVIDIA in 2013 before a standardized protocol existed. G-Sync module monitors use this protocol, so AMD cards can't use variable refresh rate on those monitors.
  
  
• VESA Adaptive-Sync — Part of the DisplayPort standard, supported by both AMD and NVIDIA (1000 series and above only).
  
  
• AMD FreeSync over HDMI — Proprietary protocol for HDMI, only supported by AMD. Developed by AMD in 2015 before a standardized protocol existed. Most monitors still use this protocol to support variable refresh on HDMI, so NVIDIA cards can't use variable refresh over HDMI on those monitors.
  
  
• HDMI Game Mode VRR — Part of the HDMI Specification, supported by NVIDIA (1600 series and above only). AMD promised support with driver update, still waiting.

Support for variable refresh rate will vary based on your graphics card and which protocols are supported by the display.