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Comment by mcv

21 hours ago

Does AMD not support Display Port? I'm not an expert on this, but that sounds to me like the superior technology.

21 comments

mcv

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tapoxi  21 hours ago

TVs don't support displayport, so it makes Linux PCs like the Steam Machine inferior console replacements if you want high refresh rates. A lot of TVs now support 4K/120hz with VRR, the PS5 and Xbox Series X also support those modes.

(Some games support 120, but it's also used to present a 40hz image in a 120hz container to improve input latency for games that can't hit 60 at high graphics quality.)

  • mcv  13 hours ago

    Why don't TVs support displayport? If HDMI 2.1 support is limited, a TV with displayport sounds like an obvious choice.

    I thought audio might be the reason, for as far as I can tell, displayport supports that too.

    • cogman10  8 hours ago

      Legacy is a bitch.

      It took a long time to move from the old component input over to HDMI. The main thing that drove it was the SD to HD change. You needed HDMI to do 1080p (I believe, IDK that component ever supported that high of a resolution).

      Moving from HDMI to display port is going to be the same issue. People already have all their favorite HDMI devices plugged in and setup for their TVs.

      You need a feature that people want which HDMI isn't or can't provide in order to incentivize a switch.

      For example, perhaps display port could offer something like power delivery. That could allow things like media sticks to be solely powered by the TV eliminating some cable management.

      5 replies →

    • pqtyw  12 hours ago

      I think it's not really an issue for 95-99% of users who uses devices with non open source drivers so there is no incentive for manufacturers to add it?

      1 reply →

    • simoncion  5 hours ago

      > Why don't TVs support displayport?

      For the same sorts of reasons that made it so for decades nearly every prebuilt PC shipped with an Intel CPU and Windows preinstalled: dirty backroom dealings. But in this case, the consortium that controls HDMI are the ones doing the dealings, rather than Intel and Microsoft.

      "But Displayport doesn't implement the TV-control protocols that I use!", you say. That's totally correct, but DisplayPort has the out-of-band control channel needed to implement that stuff. If there had been any real chance of getting DisplayPort on mainstream TVs, then you'd see those protocols in the DisplayPort standard, too. As it stands now, why bother supporting something that will never, ever get used?

      Also, DP -> HDMI active adapters exist. HDR is said to work all the time, and VRR often works, but it depends on the specifics of the display.

  • amlib  18 hours ago

    Correction, you can get 4K@120hz with HDMI 2.0, but you won't get full chroma 4:4:4, instead 4:2:0 will be forced.

    In my case I have an htpc running linux and a radeon 6600 connected via hdmi to a 4k @ 120hz capable tv, and honestly, at the sitting distance/tv size and using 2x dpi scaling you just can't tell any chroma sub-sampling is happening. It is of course a ginormous problem when on a desktop setting and even worse if you try using 1x dpi scaling.

    What you will lose however is the newer forms of VRR, and it may be unstable with lots of dropouts.