Displayport/HDMI dilema

Baggi0 · 24 Nov 2019 at 12:50

I have quite a unique problem I need help with. I have a 4K HDR OLED TV and a Dolby Atmos capable Amp and have to connect them in a certain way to get both working at the same time.

So to explain;

Firstly I have an Onkyo Amp which doesn't have HDR passthrough, so at the minute I have to run a HDMI cable from the PC to directly to my TV so I can get HDR on display 1 on the GPU.

Then because my TV doesn't pass through Dolby Atmos I have another HDMI going from the PC to the Amp and have to set up as another display (at a low resolution so not to impact anything) to get the HD sound.

Now my dilemma is that I'm getting a new GPU and they only have 1 HMDI and 3 or 4 Displayports so I would need some sort of DisplayPort to HDMI adapter but have been reading about active and passive malarky and am just confused now.

Does anyone have any knowledge of DisplayPort to HDMI? I either need one to support 4K HDR at 60hz or if not one that can just handle the HD audio.

Would something like this do the job?

https://www.amazon.co.uk/Rankie-DisplayPort-Adapter-Resolution-Converter-black/dp/B010SDZZ80/ref=sr_1_5?keywords=active+displayport+to+hdmi&qid=1574599614&sr=8-5&th=1

VincentHanna · 24 Nov 2019 at 18:29

Similar to the issue I have: https://forums.overclockers.co.uk/threads/lg-oled-c9-pc-audio-via-arc-not-earc-stereo-only.18870473/

TL/DR - Displayport won't give you decent audio

Baggi0 · 27 Nov 2019 at 19:10

VincentHanna said:
Similar to the issue I have: https://forums.overclockers.co.uk/threads/lg-oled-c9-pc-audio-via-arc-not-earc-stereo-only.18870473/

TL/DR - Displayport won't give you decent audio

Thanks for the reply.

Im pretty stuck then unless I get a new amp that’s supports HDR.

Come to think of it when you tried DisplayPort to HDMI, could you get 4K HDR? If so I can just use the HDMI for sound and the DP/HDMI for visuals.

VincentHanna · 27 Nov 2019 at 19:13

Didn't try it, because I need G-sync to my LG C9 TV, which is only supported via the HDMI output.

Even though Gsync to monitors works via DisplayPort.

Baggi0 · 27 Nov 2019 at 19:22

VincentHanna said:
Didn't try it, because I need G-sync to my LG C9 TV, which is only supported via the HDMI output.

Even though Gsync to monitors works via DisplayPort.

Ok cool, I’ll probably get one ordered then and send it back of it doesn’t work.

Was yours similar to the one in the link I posted?

I don’t understand why GPUs don’t have 2 HDMIs. Do we really need 4 DisplayPorts?!?

Baggi0 · 7 Dec 2019 at 16:39

Just an update on this.

I bought that adapter I linked above and it solved my problem in the end.

Firstly I tried DisplayPort to HMDI to see if I could get HDR and all the chroma settings needed whilst it did kind of work it didn’t fully as I could only select 420 chroma. With HDMI though you get 420, 422, 444 and RBG and as I use 444 when not playing HDR games that wasn’t going to work for me.

So I went the other route and tried DisplayPort to HDMI for the sound and that worked perfectly. I tested out Dolby Atmos and other HD audio formats and everything worked fine.

So in summary if you have an amplifier that doesn’t have HDR but can decode HD audio you can use your GPU to extend the display and use a HDMI cable to go to your TV for 4K HDR and DisplayPort with a HDMI adaptor to the Amp for HD audio.