AMD & HDMI 2.1

So, I bought an RX 7600 XT, when I was still using my 10 year old TV. Recently upgraded to an LG C4, reading the news about AMD support for HDMI 2.1 on Linux, I also went looking for a DP->HDMI adapter and found one that claims to even support VRR. After a week of getting random audio cuts, suspecting the adapter was at fault, I went pure HDMI...

To my surprise, I could run at 4K 120hz with VRR and HDR. Doesn't that require HDMI 2.1?

24 points · 10 comments · view on lemmy.world

10 Comments

Sproutling@lemmy.ml · 15 pts · 1y (9 replies)

You're probably running in non-RGB 4:4:4. Quick test is to have some red console text against a gray background and if the text is fuzzy with compression artifacts at the edges, then it is not 4:4:4. You can check what mode your TV is in by clicking the green button with the two dots seven times.

take6056@feddit.nl · 1 pts · 1y (8 replies)

Thanks for the tip. It says YCbCr420. Anything I can do to improve that?

Sproutling@lemmy.ml · 12 pts · 1y (7 replies)

Nope, you're running into the dreaded AMD HDMI 2.1 limitation. The situation just sucks.

take6056@feddit.nl · 3 pts · 1y (6 replies)

I would kindly ask the HDMI forum to point me in the direction of a DP to HDMI adapter that supports VRR or FreeSync. They seem so motivated to gain more funds from royalties, surely they know how to persuade me.

Sproutling@lemmy.ml · 7 pts · 1y

Fuck those guys. I really wish LG would support DP a bit more in their products.

Zamundaaa@discuss.tchncs.de · 4 pts · 1y (1 reply)

The real question is though... if you haven't noticed the TV using YCbCr420 until it was pointed out to you, why would you spend more time looking into it?

take6056@feddit.nl · 1 pts · 1y

In retrospect, I have noticed. Thought it was badly compressed content.

vividspecter@lemm.ee · 2 pts · 1y (2 replies)

DP to HDMI adapter that supports VRR or FreeSync.

Here you go: https://www.amazon.com/Cable-Matters-102101-BLK-Computer-Adapter/dp/B08XFSLWQF

It's slightly quirky, but it does work. Although I don't use HDMI audio so maybe you're already using the same adapter.

take6056@feddit.nl · 1 pts · 1y (1 reply)

It's not the adapter I bought, but also seems VRR is lacking:

"VRR/G-Sync/FreeSync are not supported."

Have you experienced otherwise?

vividspecter@lemm.ee · 1 pts · 1y

It works, but it only works on Linux so they don't advertise it. You may need to update the firmware to get the best experience too.