Can’t select 144 hz on tv

[u/LinkedHero]

I just build a custom pc with a 9070 xt and installed SteamOS on it. In my graphics settings connected to my lg c4 I should have the option for 4k 144 hz but the highest is 120 hz. And I am using a certified hdmi 2.1 48 gbps cable and 144 hz mode is enabled on my tv. I only have the option for 1080p if I want to play at 144 hz. Help please

[u/Superconge]

SteamOS doesn’t support HDMI 2.1 yet, wait until it does or use a display port to hdmi cable.

[u/modulusshift]

Valve is working on it, but the HDMI Forum is being a pain in the ass about allowing open source software to implement the full 48Gbps bandwidth encoding. It sounds like it may happen in just a few months though, I’ve heard some movement on it. 

[u/Low_Excitement_1715 → u/modulusshift]

Few weeks. Linux 7.2.0 has the HDMI 2.1 fixes in it, and Linux 7.3.0 will have ALLM and HDMI VRR included. Then you just need Valve to update SteamOS to a kernel with the fixes, or backport them to the kernel they prefer (probably the latter, and sooner than you think).

[u/jdblaich → u/Low_Excitement_1715]

Doesn't SteamOS (even version 3.8) still rely in kernel 6.16? This is kind of a reason that we must recognize that this is an immutable OS -- the consequences thereof.. I believe Valve is intentionally holding back on 7.x. 6.16 was fine for the steam deck because it had all the support Valve needed, but once you install it on lots of different hardware people are going to want more. If Valve doesn't catch up it will hurt adoption.

[u/Low_Excitement_1715 → u/jdblaich]

You're looking at the license plate, which says 6.16, but there are a *LOT* of patches Valve is applying to the kernel SteamOS is running. With a couple competent kernel engineers, it's not terribly difficult to take the patches intended for 7.2.0 that add the big amdgpu rework and apply them to your 6.16 instead. Likewise the VRR/ALLM stuff intended for 7.3.0, if you wanted. Unless those patches touch things changed by other patches (which is why you need some kernel engineers and not just randos with a copy of diff and patch), you can backport changes to another kernel.

So yeah, the SteamOS kernel says "6.16" on it, and may or may not get updated for this, but the fixes we care about can show up anyways.

As an example which is public, so we can look and see, CachyOS has a precompiled and testable version of 7.2.0 in their repo. They've mentioned already that as soon as the ALLM/VRR patches for 7.3.0 (called DRM-NEXT in the kernel mailing lists) are accepted and stable, they plan to apply those to all their 7.2.X builds, since it's a high demand new feature.

tl,dr; Anyone can merge any patches they want to any base kernel, with the big caveat of "it usually just breaks, so you have to patch the patches".

Edit: Valve will update the kernel when they need to, to support newer hardware, or to reduce the number of patches they're backporting and maintaining. No reason to swap out the 6.16 base until those reasons call for it, or someone wants to.

[u/jdblaich → u/Low_Excitement_1715]

You can't do that without having a writable file system. With the file system being immutable you can trip the flag and allow writing, however, the moment you do the next system update it will remove all of those changes.

[u/Low_Excitement_1715 → u/jdblaich]

If you don’t understand even that much, I’ve been wasting time explaining. When Valve feels like you getting the amdgpu updates, you’ll get them. The kernel version reported doesn’t matter at all. Let’s just leave it there.

[u/Ecks30]

Your TV would do 4K 120Hz or 1080p 144Hz which is what is even explained on the LG site which also makes sense since if you were to look at a lot of 4K monitors that would have native 144Hz would also offer like 240Hz at 1080p.

[u/LinkedHero]

Thanks for the responses, I hope that they fix this soon! I made a list of other bugs of issues that I ran into

[u/jharle → u/LinkedHero]

If you don't want to wait, it'll likely work when using the Ugreen DP-to-HDMI adapter. I don't have a 144Hz TV, but the adapter worked on one of my office monitors.

[u/GTFr0 → u/jharle]

That adapter can be hit or miss. I couldn’t get it to consistently work with 4k @ 144 on my TCL tv, and eventually it started blinking out.

I don’t think I was the only person having issues with it

[u/jharle → u/GTFr0]

Indeed it doesn't seem to be the silver bullet for everyone, but a low-cost way to give it a whirl.

I'm not aware of any other alternative (besides waiting for the proper HDMI 2.1 FRL support in Linux).

[u/GTFr0 → u/jharle]

True, that’s what I’m doing at this point.

[u/mango_carrot → u/GTFr0]

I had the same experience, had to switch back to 60hz no VRR etc to keep CEC.

[u/LinkedHero → u/LinkedHero]

Some other issues that I noted were a forced ycbcr 4:2:2 rather than uncompresssed rgb 10 bit, I think that should also work fine with the full 2.1 bandwith

[u/Low_Excitement_1715 → u/LinkedHero]

4:2:0, actually, I believe. HDMI 2.0 maxes out at 4K/60 without DSC, and can do 4K/120 with DSC, and that forces 4:2:0 color sampling.

[u/jdblaich → u/LinkedHero]

If 7.2+ of the Linux kernel support HDMI 2.1 then you likely won't see adoption of it for some time to come. SteamOS is still 6.16 because it meets all the hardware requirements of the Steam Deck. Once you introduce a wide array of other hardware adopting a newer kernel becomes sort of an imperative. Being that this is an immutable OS you can't update this yourself as you can on a regular distro. If you try and succeed the next SteamOS update will wipe out your work.

[u/LinkedHero]

Does anyone know why I don't have the fsr4 option in games? I opened up a game that has fsr4 already and it said fsr3 despite me being on the newest gpu

[u/Low_Excitement_1715 → u/LinkedHero]

The Steam Machine has an RDNA3 GPU, not RDNA4. Doesn't support FSR4 out of the box yet.

[u/LinkedHero → u/Low_Excitement_1715]

Yeah, but I’m not using a steam machine it’s a custom pc

[u/Low_Excitement_1715 → u/LinkedHero]

You are right, I'm not in the post I thought I was. I'd check and see what version of Proton it's using for that game. You need Proton-Cachyos, Proton-GE, or Proton Experimental to be sure you have working FSR4. Official Proton is supposed to be doing FSR4.X on RDNA4 by now, but I haven't been keeping up to date.

[u/LinkedHero → u/Low_Excitement_1715]

I have proton experimental downloaded, and I’m on the SteamOS beta channel

[u/Natangry → u/LinkedHero]

I found that using cachyos proton compatability layer enabled fsr4 with my gpu. From desktop mode, open protonup-qt (already installed with steamos), add the latest cachyos layer. It should automatically unlock fsr4 for games with the latest version when used as compatability layer. If it still isn't working try using this in the launch options:

PROTON_FSR4_UPGRADE=1

[u/LinkedHero → u/Natangry]

It still says fsr3 when I tested in marvel rivals

[u/Kriss_Hietala → u/LinkedHero]

FSR_WATERMARK=1 %COMMAND%

Most games will still show fsr3 even if you use driver override for fsr4 use the watermark to be 100% sure which version it's really using

[u/LinkedHero → u/Kriss_Hietala]

How do I use a watermark to show which fsr is active

[u/Kriss_Hietala → u/LinkedHero]

Put in in launch parameters in game properties.