CONFUSING about DP2.1, HDMI2.1, DSC..read my discussion pls

[DISPLAY PORTER]

i always use display port, on my old asus pg278qr, 165hz, dsr/dldsr work fine

i recently bought new pg 32uqxr.
started with stock dp2.1, after some struggle i see can enable 160hz with dsc, but with dsc cannot anymore enabled DSR.

today after read a lot i see, if i disable dsc, and set monitor to 144hz, i can enable dsr...

but read more and more i see my 4080 rtx only support dp1.4a, and hdmi 2.0

so i immediatly remove display port 2.1, and connect for first time HDMI 2.1 cable.

first thing i notice, i can finally use 160hz in 4k witout DSC with hdmi...but

i cannot more use dsr/dldsr anymore.

now i want know, because 4080 only support dp 1.4a, and hdmi 2.0, if the choice of plug hdmi is the best way

imean, display port still the best example for fps games, or the thing 4080 only support 1.4a, make hdmi 2.1 the best choice?

for dsr i have no more hope, i dont want change cable only for use it, if someone tell me hdmi are superior

sorry for my english

 

[nlel1975]

I can run 240 Hz over both DP 1.4a and HDMI 2.1 with dsc. My graphics card supports DP 2.1 and HDMI 2.1. I am sure the 4080 would too. My monitor supports DP 1.4a and HDMI 2.1.

 

[DISPLAY PORTER]

I can run 240 Hz over both DP 1.4a and HDMI 2.1 with dsc. My graphics card supports DP 2.1 and HDMI 2.1. I am sure the 4080 would too. My monitor supports DP 1.4a and HDMI 2.1.

me too, my 4080 only support dp 1.4, but i use 2.1 cable witout problem

but for dsc, dp2.1 cannot reach 160hz witout it
hdmi 2.1 cable can reach 160hz witout dsc

and i see 4080 zotac manufactrer site say about 3xdp1.4, and 1x hdmi 2.0

 

[nlel1975]

and i see 4080 zotac manufactrer site say about 3xdp1.4, and 1x hdmi 2.0

Yeah I saw that too, I'm surprised I thought all modern GPU supported DP 2.1. If your graphics card only supports DP 1.4a that will be why you can't run 160 Hz without dsc.

 

[DISPLAY PORTER]

Yeah I saw that too, I'm surprised I thought all modern GPU supported DP 2.1. If your graphics card only supports DP 1.4a that will be why you can't run 160 Hz without dsc.

yes...so is better use hdmi 2.1 cable at this time?

imean, hdmi 2.1 and dp 1.4 are basically the same thing?

no visual loss, or anithing?

 

[nlel1975]

no visual loss, or anithing?

Yeah DSC is lossless. I run HDMI 2.1 with my 7900 XTX and DP 1.4 with my Mac mini M4. Both running at 240 Hz.

 

[DISPLAY PORTER]

Yeah DSC is lossless. I run HDMI 2.1 with my 7900 XTX and DP 1.4 with my Mac mini M4. Both running at 240 Hz.

idk why i cant run dsr/dldsr with hdmi cable.

i can do it with dp2.1 cable, only witout dsc

but witout dsc i cant reach 160hz.

so thing is stay with dp2.1 and use dsr when i want, disabling dsc and set to 144hz

or use hdmi2.1 cable, reach 160hz witout dsc, but cannot use dsr/dldsr

 

[Baddass]

The differences between the monitor and graphics card ports is confusing matters here

Your graphics card has a DisplayPort 1.4 output and an HDMI 2.1 output (not HDMI 2.0, that was upgraded to 2.1 since the RTX 30 series). The PG32UQXR has a DisplayPort 2.1 and HDMI 2.1 ports.

There’s no point using a DP 2.1 cable when your card only support DP 1.4. It won’t make any difference compared with a normal DP 1.4 cable. Obv there’s no harm using a DP 2.1 certified cable if you have one, but it’s just confusing matters I think.

If the screen offers you the option to disable DSC in the OSD menu then you will be limited to 4K at 98Hz max if you want to run at 4:4:4 RGB chroma over DisplayPort 1.4. If it’s letting you select 144Hz, it will be dropping chroma at the same time which is definitely visually noticeable and not recommended. If you’re going to disable DSC and use DisplayPort 1.4, I’d stick to 98Hz max refresh rate and RGB chroma. You’d have to drop to 8-bit colour depth but that shouldn’t be noticeable. DSR will only work if you disable DSC on this monitor.

If you’re using HDMI 2.1, that will support up to 4K 120Hz at 4:4:4 chroma and 10-bit colour depth as it has more bandwidth than DP 1.4. If you really want to disable DSC (see below point), I’d use that.

I’m not sure why DSR wouldn’t be available though when using HDMI without DSC, unless it’s a weird NVIDIA thing with HDMI 2.1.

A question though - do you really need to use DSR on this screen? It’s already 4K resolution and it’s unlikely to add much benefit in image detail as a result. DSR is more useful for lower res screens. I expect using DSC and being able to use the full refresh rate will provide a better visual experience overall anyway.