The TL;DR is that the organization that controls the HDMI standard won’t allow any open source implementation of HDMI 2.1.
So the hardware is fully capable of it, but they’ll get in trouble if them officially implement it.
Instead it’s officially HDMI 2 (which maxes out at 4k @ 60Hz), but through a technique called chroma sub-sampling they’ve been able to raise that up to 4k @ 120Hz.
However there are some minor reductions in picture quality because of this, and the whole thing would be much easier if the HDMI forum would be more consumer friendly.
In the meantime, the Steam Machine also has display port as a completely issue free display option.
I would normally prefer no hdmi at all, but it’s an entry point device so it doesn’t really make sense to do that.
DisplayPort rocks
Yeah fuck the video codec mafia and all these proprietary shits like HDMI
Fun fact, all of the audio codes are proprietary too. You won’t find a HDMI surround sound splitter on Aliexpress. Say no to HDMI, say no to E-ARC.
You know it reminds me of the academic publishing mafia of Elsevier and the like
I used to find it took forever to start showing a picture compared to HDMI on my PC. Getting a new GPU so maybe that will improve things.
Is this why DisplayPort looks better for me on Linux???
Yes. DP is the right choice for civilized people.
Yep it’s pretty much better in all regards.
The only downside is no ARC support, but I suppose support for that is pretty hit or miss anyway.
With TVs starting to get USB-C inputs, which are displayport under the hood, hopefully HDMI fucks off.
Ballparking but it will likely take closer to a decade than not for that to actually happen… and I am still not optimistic. And there are actually plenty of reasons to NOT want any kind of bi-directional data transfer between your device and the TV that gets updated to push more and more ads to you every single week.
The reason HDMI is so successful is that the plug itself has not (meaningfully?) changed in closer to 20 years than not. You want to dig out that PS3 and play some Armored Core 4 on the brand new 8k TV you just bought? You can. With no need for extra converters (and that TV will gladly upscale and motion smooth everything…).
Which has added benefits because “enthusiasts” tend to have an AV receiver in between.
The only way USB C becomes a primary for televisions (since display port and usb c are arguably already the joint primary for computer monitors) is if EVERY other device migrates. Otherwise? Your new TV doesn’t work with the PS5 that Jimmy is still using to watch NFL every week.
Countdown until some community member patches 2.1 support in
Not that easy.
To get HDMI 2.1 support for the Gabe Cube itself essentially requires kernel level patches. Which on a “normal” Linux device is possible (but ill advised) but on these atomic distros where even something like syncthing involves shenanigans to keep active week to week? Ain’t happening. Because HDMI is not just mapping data to pins and using the right codecs. There are a LOT of handshakes involved along the way (which is also the basis for HDCP which essentially all commercial streaming services utilize to some degree).
There ARE methods (that I have personally used) to take a DP->HDMI dongle and flash a super sketchy Chinese (the best source for sketchy tech) firmware to effectively cheat the handshakes. It isn’t true HDMI 2.1 but it provides VRR and “good enough for 2025” HDR at 4k/120Hz. But… I would wager money that is violating at least one law or another.
So expect a lot of those “This ini change fixes all of Windows 11. Just give money to my patreon for it” level fixes. And… idiots will believe it since you can use a dongle to already get like HDMI 2.05 or whatever with no extra effort. And there will likely be a LOT of super sketchy dongles on AliExpress that come pre-flashed that get people up to 2.09 (which is genuinely good enough for most people). But it is gonna be a cluster.
And that is why all of us with AMD NUCs already knew what a clusterfuck this was going to be.
There are also ways to fake the handshake in software. I personally did not try that but from what I have seen on message boards? It is VERY temporary (potentially having to redo every single time you change inputs on your TV/receiver) and it is unclear if the folk who think it works actually tested anything or just said “My script printed out ‘Handshake Successful’, it works with this game that doesn’t even output HDR!”
a super sketchy Chinese (the best source for sketchy tech)
Russian is also good
Cable Matters sells plenty of different DP->HDMI 2.1 adapters that work with VRR. The main issue here is that you won’t get CEC if you use those.
If would need to be patched in on Linux kernel level, which is annoying to say the least.
