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Comment by foresto | Hacker News Reader

Is HDMI really a roadblock to gaming when DisplayPort exists?

It's a blocker if you want to use a TV, there are almost 0 TVs with DP. This HDMI licensing crap is also the reason a Steam Deck can't output HDMI > 4K@60 unless you install Windows on it.

Aren't there some hardware dongles to translate from DP to HDMI?

Last I checked, even the best ones that are high quality don't support VRR.

A recent one seems to work with VRR: https://www.reddit.com/r/linux_gaming/comments/1pkdfcm/ugree...

DP1.4 though, so you're still going to need compression.

Yup this works but there's as of yet no HBR13.5 or better input so you're not getting full hdmi 2.1 equivalent. But if you don't care about 24 bits per pixel DSC then you can have an otherwise flawless 4k120hz experience.

https://trychen.com/feature/video-bandwidth

Wow that's awesome work in that post! I've also bought a few things from UGreen now, they're great.

Thanks for this link! I'd heard of the CableMatters dongle but this seems like a better route to go assuming the patches are accepted.

DP is something like a free superset of HDMI, so you can use a fully passive DP-HDMI cable. Obviously the feature set will be limited, but it will work.

DP however can't transfer audio, which doesn't matter for a desktop but matters a lot for a TV.

DisplayPort can absolutely carry audio; see Wikipedia: https://en.wikipedia.org/wiki/DisplayPort

> DP is something like a free superset of HDMI, so you can use a fully passive DP-HDMI cable.

No, it's not, the protocol is completely different (DP is packet-based while HDMI traditionally was not, though AFAIK HDMI 2.1 copied DP's approach for its higher speed modes). When you use a passive DP-HDMI cable (which AFAIK is not fully passive, it has level shifters since the voltages are different), it works only because the graphics card detects it and switches to using the HDMI protocol on that port; if it's not a dual-mode port (aka "DP++" port) it won't work and you'll need an active DP-HDMI adapter.

> DP however can't transfer audio, which doesn't matter for a desktop but matters a lot for a TV.

On the desktop I'm using to type this message, I use the speakers built into the DP-connected monitor (a Dell E2222HS). So yes, DP can and does transfer audio just fine. If it couldn't, then active DP to HDMI adapters wouldn't be able to transfer audio too.

The only thing DP doesn't have AFAIK is ARC, which might matter for a few more exotic TV use cases, and HEC, which AFAIK nobody uses.

You may be thinking DVI, which is a subset of HDMI, and lacks audio, and can have a passive DVI->HDMI connection.

If you have a TV with low latency for gaming, 4K, and 120+hz, then you have a really expensive TV, and you likely care about quality. I'd reckon most of this popultion also owns a separate monitor for PC gaming.

Up until a year or two ago, the majority of monitors (and graphic cards) used DisplayPort 1.4 and HDMI 2.1. With HDMI 2.1 (42 Gbps) having more bandwidth than the DisplayPort (26 Gbps).

This is my case with my relatively new/high-end RTX 4080 and OLED monitor. So until I upgrade both, I use HDMI to be able to drive a 1440p 240hz 10-bit HDR signal @ 30 Gbps.

I had said I wouldn’t upgrade from my RTX 3080 until I could run “true 4K”.

I finally got the 240hz 4K uncompressed but it required buying a $1300 Asus OLED monitor and the RTX 5090. It looks amazing though, even with frame gen. Monster Hunter had some particularly breathtaking HDR scenes. I think it uses DisplayPort 2.1? Even finding the cable is difficult, Microcenter didn’t have them in April and the only one that worked was the one that came with the monitor.

The Chinese tech manufacturers are so sick of the HDMI licencing mafia that they've developed their own replacement for it:

https://www.techpowerup.com/335152/china-develops-hdmi-alter...

I want to play games on the same fancy lg tv I use with my consoles. I just checked and it does not appear to have displayport.

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