XPS 13 9300 - HDR issue while connected to TV

@kan84  HDMI 2.0 imposes a bit of limitation here.  When running 4K resolution, there are 3 separate signal varations: 60 Hz refresh rate (rather than 24-30 Hz), HDR color space (instead of SDR), and full chroma (4:4:4).  You can use any 2 of those at the same time, but you can't have all 3.  I don't know if the system supports using reduced chroma, such as 4:2:2 or 4:2:0, and if it doesn't, then you can't run 4K 60 Hz HDR all at the same time.  This is a bandwidth limitation of HDMI 2.0.  DisplayPort 1.4 would support 4K 60 Hz HDR with full chroma, but you don't have a DisplayPort 1.4 input to use.

@kan84  If there's a way to see or change chroma, it would likely be within Intel HD Graphics Control Panel (or Command Center, depending on driver version).  You could try creating a custom resolution to see if that gives you some additional flexibility.  The other possibility, which now actually seems likely now that it's just occurred to me, is that even if your system supports DisplayPort 1.4 and the adapter can output HDMI 2.0, it doesn't mean that the adapter can accept a DisplayPort 1.4 signal and therefore that your system would negotiate DP 1.4 with it.  The adapter might be limited to DisplayPort 1.2.  USB-C to HDMI adapters typically incorporate an active signal converter chip since USB-C ports typically do not support sending a native HDMI signal.  (There is technically an "HDMI Alt Mode" standard, but it's not widely implemented as far as I know.  DisplayPort Alt Mode is very widely implemented.)  So what happens is that the system sends a DisplayPort signal that gets switched to HDMI within the adapter.  But that means that the system negotiates its DisplayPort revision with the adapter.  Some USB-C to HDMI 2.0 adapters existed to allow running 4K 60 Hz SDR to TVs, which couldn't be achieved with an older HDMI revision on the output side but only requires DisplayPort 1.2 on the input side.  And DisplayPort 1.2 doesn't formally support HDR.

Just from a quick search I found this adapter that specifically mentions HDR support, although I've never even heard of that brand.

@kan84  Ok, found a similar adapter from StarTech here.  StarTech has a solid reputation for reliable, quality products.  I've bought several of their products over the years and have had consistently good experiences.  I can also say those things about Anker, which makes the adapter you have, but it seems the product you have simply wasn't designed to support your use case.  This one does seem to be, so you might want to give it a try.

@jphughan  Thanks for the quick response, anyway to check chroma in windows 10 system setting? Will try reducing the refresh rate and see if it helps.

I was hoping to see some 4k 60hz hdr videos on youtube which does not work properly on shield tv.

Hi @kan84, did you get to output 4K 60Hz HDR in the end? I'm considering to buy this laptop for some HDR experiments.

@Samuel0507 I was able to connect to my tv with 4k hdr 60 hz. Make sure you get a hdmi 2.0b adapter.

This should work with newer XPS 13 9310

@kan84 Thanks man!

@Samuel0507Forgot to mention, HDR movies on netflix desktop app crashes the app.

I majorly tested youtube 4k60hz hdr videos and they worked fine if you use browser which supports 4k60hz like Edge etc.

@kan84 Thanks for the info.

I'll probably just use the laptop to run some HDR color benchmark, hope there won't be any compatibility issue then.