Weird display issues

[Jae-So]

Have an issue with my current set up.

I have the following setup, running from a Zotac GTX 1070 mini.
- DP to HDMI to 4K 65 inch TV (HDMI MHL port. Note this TV doesn't have HDR.
- HDMI to Oculus Rift

It seems when I use the DP to HDMI cable the only HDMI port that will run 4k/60 is the HDMi (MHL) port.
I have tried running HDMI to HDMI on the TV and in this configuration other ports can run 4k/60 including the HDMI (DVI) port. The issue is the lone HDMI port onny 107 is being used for the Rift.

I'm happy to use the MHL port but I notice that MGS V shows me a Green/oddly scaled screen when running at 4k, even though it works fine on the supersampled screen. This issue isn't present when using HDMI to HDMI.

Questions:
1) What's the best setup to use here? I am thinking about using a DP to HDMI converter for the Rift and just sticking to the HDMI for the TV via HDMI (DVI) port.
2) Is there anything inherently wrong in using the HDMI (MHL) port? From what I can tell the only difference is it doesn't allow UHD colour so it doesn't allow 4:4:4.

Thoughts? Thanks in advance.

 

[Jae-So]

So it seems at the very least that I should run via HDMI. Works perfectly at 4k/60 on my HDMI (DVI) port.
In fact, I'm thinking about just running some of my games at 1440p/60 on the TV as it looks about as good to me. The DP to HDMI setup wasn't letting me run 1440p/60 either so this seems the better setup.

 

[Jae-So]

So guys I worked around this issue by using a displayport to HDMI adapter on my Rift and running my PC through HDMI. I have however no changed the layout of my roommand ideally need to use the HDMI port for the Rift.

Anyone have any clue as to why a Displayport to HDMI cable (rated up to 4k) doesn't seem to work on most of the HDMI ports?

 

[Jae-So]

I guess this has never happened to anyone else?

 

[Habakkuk]

Displayport is different to HDMI - it requires a active signal.

Presumably, it's not getting a device_active return message.

I'm assuming you're using a passive rather than active adapter.

 

[Jae-So]

Displayport is different to HDMI - it requires a active signal.

Presumably, it's not getting a device_active return message.

I'm assuming you're using a passive rather than active adapter.

How do I check that signal?

Yeh it must be passive, the thing is why did it work with my Rift (I need to order a new one as I have smashed it accidentally).
Does the Rift not require an active adapter.

 

[Jae-So]

Thanks for your help, just ordered an active one that says supports 4k@60. It arrives Sunday and will update here.

 

[Jae-So]

@Habakkuk
Thabks for your help, switching to an active one seems to have solved the problem.
Just need an HDMI extension for the Rift now.