cancel
Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for 
Search instead for 
Did you mean: 

Graphics Cards

tattoofreak
Adept I
‎10-21-2022 03:06 AM

Help: VRR (Variable Refresh Rate) not working

I'm totally new to the VRR (Variable Refresh Rate) topic so please have patience if I do not know everything about it. Before posting my question here I want to note that I've tried to read and learn as much as possible about VRR and despite of confusing readings it seems I learned also a couple oft things:

  • There's a big difference between HDMI Forum VRR and FreeSync
  • VRR over HDMI is not handled the same way as VRR over DisplayPort
  • Windows and Linux do handle VRR differently, in a way that Windows does not support HDMI Forum VRR but only Freesync. For Linux it was said that the native kernel drivers do not support FreeSync but only HDMI Forum VRR, but, if this ever was true, has clearly changed according to this topic.
  • Linux supports HDMI Forum VRR from RX6000 series on but only in a HDMI 2.0 environment and not in a HDMI 2.1 environment.
  • On Linux, HDMI Forum VRR and FreeSync gets enabled by default from Linux kernel 5.18 on.

All that said I must say that most of the things I have read are about two years old so I'm wondering if over the years has changed anything and now I would like to post my question.

My main issue is the following:

I have the following hardware setup, all hardware is HDMI 2.1 capable:

  • Linux HTPC x86_64 with AMD Radeon 6800XT graphics card and Linux kernel 5.18.19
  • LG OLED55GX9LA TV (which is HDMI Forum VRR and AMD FreeSync ready)

Unfortunately I am not able to make HDMI Forum VRR work. On the LG TV, according to this topic, I did set the following settings to make sure HDMI Forum VRR is enabled and AMD's native FreeSync is disabled:
AMD FreeSync --> Disabled
Instant Game Response --> Enabled

FreeSync on the other hand works without any issues but is not an option to me because later I want to include my Onkyo TX-NR6100 AV receiver which does support HDMI Forum VRR but does not support FreeSync.

Any hints what the problem could be? Is it really still the case that HDMI Forum VRR is not supported on AMD graphics cards in Linux for HDMI 2.1 but only for HDMI 2.0?

Clearing this things up would help me a lot. Thank you in advance!

0 Likes
2 Replies
cvzone
Adept III
‎10-27-2022 05:20 AM

HDMI VRR and Freesync are different standards but they do the same thing. If you can use freesync, use freesync. (try a direct HDMI connection and use ARC/eARC with your AVR as workaround)

Until now the RX6000 Series does not support HDMI VRR over FRL connections (4K120) but on TMDS (4K60) it is working fine.

If it's a driver or hardware problem? Nobodys knows, because AMD is ignoring this. (i guess not enough HDMI VRR users out there, because most TVs support freesync as well)

0 Likes
tattoofreak
In response to cvzone
Adept I
‎10-28-2022 04:45 AM

@cvzoneThank you very much for confirming that HDMI VRR is not working on 4K/120Hz currently. Well, I already messed around a lot now with the ARC/eARC workaround. It basically works but has also two downsides in my case:

  1. Whenever the OS is switching resolution, an annoying notification popup comes up on the LG TV, saying "The Instant Game Response is launched". Depending on the application(s) you are using on your PC, this can get very frustrating as LG does not give an option to disable notifications. There are a lot of uers having this problem, especially PS5 users, ending up just disabling VRR:

    https://nerdburglars.net/hardwareguides/lg-cx-flickering-instant-game-response-launched-on-ps5/

    https://www.reddit.com/r/OLED_Gaming/comments/kj7kym/instant_game_response_is_launched/

    https://www.reddit.com/r/OLED_Gaming/comments/nws7uy/any_fix_yet_for_instant_game_response_is_launch...

    However, in my case it is really annoying too, but fortunately in my case it's really not a permanent popup as other users have reported. Really just when resolution changes.

  2. Before switching to eARC I could turn the sound volume up and down smoothly and without any interrupts. Now, with eARC enabled, changing the sound volume interrupts the audio signal as long as I hold down the volume up/down button. The sound comes back immediately when I release the volume button though. This also is a really annoying downside because I cannot decide "on the fly" when I want to release the volume button. In summary it takes more time and button presses to set the volume to an according suitable level. Plus, as you can imagine, it's also very disturbing when the audio output gets interrupted while changing the audio volume level.

I really hope AMD will change its mind and support HDMI VRR on 4K/120Hz, because I think there are barely AV-receivers supporting FreeSync, if any.

0 Likes