GTX 1080, a monitor and a TV.

willhub · 27 Feb 2018 at 22:37

Having a few problems here.

My Samsung TV works fine on its own (HOWEVER when I enable HDR in display settings the screen goes blank and looses signal), my AOC monitor works fine on its own also.

The issue is when both connected, TV via HDMI and AOC via DP, what happens is my screen keeps flickering and re-adjusting to some degree, the mouse keeps centering and generally the PC isn't very responsive.

Anyone have any ideas how to fix this?

willhub · 28 Feb 2018 at 00:20

Think I fixed it, had the thing plugged into HDMI 3 (ARC), maybe that's why. Now I've got it in 1 it's fine, however enabling HDR the screen is very dark!

**EDIT** - as soon as I put this then tried a game, 4k @ 60Hz and the monitors become blank, can't even get the TV to show now, doing my head in this!

imginy · 28 Feb 2018 at 00:39

Is it to do with the limit of the hdmi?

I don't have hdr or anything yet but think you need to choose either 422 with 10 bit or rgb with 8 bit.

willhub · 28 Feb 2018 at 00:43

Not sure what you mean? Could that be why the screen is messing up between monitors? have to run 4k at 24Hz at the moment, also tried a game, GTA V and the core clock was only at 1.2GHz? Can't work out what's causing it.

imginy · 28 Feb 2018 at 00:49

willhub said:
Not sure what you mean? Could that be why the screen is messing up between monitors? have to run 4k at 24Hz at the moment, also tried a game, GTA V and the core clock was only at 1.2GHz? Can't work out what's causing it.

Just wondered if it's trying to run 4k 60hz hdr 10bit colour rgb/ycb444? I believe this will not run it's too much for the hdmi.

from what I read if this is your problem you need to drop the colour to 8bit or change to ycb442.

willhub · 28 Feb 2018 at 01:00

imginy said:
Just wondered if it's trying to run 4k 60hz hdr 10bit colour rgb/ycb444? I believe this will not run it's too much for the hdmi.

from what I read if this is your problem you need to drop the colour to 8bit or change to ycb442.

I turned the HDR off as screen was too dark and in GTA V when I turn tried it, switching from 24hz toanythto higher caused black screen.

In Windows properties both displays are recognise as generic pnp monirors should that be the case?

And how doi adjust the colours?

imginy · 28 Feb 2018 at 01:10

The only thing I can suggest is go to your nvidia control panel under display settings go on change resolution and try changing the output colour depth and output colour format.

willhub · 28 Feb 2018 at 08:28

Is it normal for GTA V to only do 24Hz at 4k?

**edit**

I tried 50Hz and the screen at least came on in game, then kept flashing to a blank screen and back on, eventually both monitors went off.

Could it be a faulty card? Monitor + TV both work individually just not together. Really annoying this.

passifid · 28 Feb 2018 at 08:37

No it's either your screen or the cable. You need to see which ports are able to do 4k 60 , most hdmi won't. Not all display port cable will. I had a problem with using 4k60 and getting the screen go black every 5-30 seconds it was caused by my cable not fulfilling the requirements for the bandwidth

passifid · 28 Feb 2018 at 08:39

If you are at all unsure of what's bieng chatted then just post the exact TV model so we can check the outputs and match them with your requirements best as possible

Squid Vicious · 28 Feb 2018 at 09:03

Assuming it's a Samsung UE49MU6400 based on post history https://forums.overclockers.co.uk/t...t-query-and-need-calibration-advice.18804986/

Modern TV so it's not that it's running over hdmi 1.4. Cable issue? Maybe... there are 2 types of hdmi cable - standard and high speed - of which standard became obsolete years ago - but still a chance I guess.

[EDIT] Definitely worth checking with another cable if you have a spare hdmi anywhere - a low quality uncertified cable could well be culprit.

Squid Vicious · 28 Feb 2018 at 09:06

Take a look at this thread https://forums.overclockers.co.uk/threads/mini-review-samsung-40ku6400-as-a-monitor.18756127/

The first post describes setting up a similar samsung tv so worth checking those for a start.

Demon said:
This is just a small mini review of the Samsung UE40KU6400 UHD TV used for PC / Console duty.

Setup and IQ Tweaking
For PC use, I am feeding it from an ASUS Strix GTX970 via a HDMI 2.0 cable.
The input has been set to 'PC' which automatically defeats just about all processing options, and then the HDMI colour space expanded to UHD Color (4:4:4).The Nvidia control panel was then used to set 8 bit colour and 4:4:4 colour encoding.
I confirmed all this using this simple test on a webpage ((4:4:4 Check).

The next step is due to my photography hobby I calibrate all my displays, in this case using an i1 Display Pro. As per the DF Review, you do indeed need to set the white balance to WARM 2 and from there it's just a small tweak of the RGB channels. The out the box calibration isn't too bad at all, if I switch between a default colour profile and my calibrated profile, the differences are only marginal.
I confirmed using imaging resources simple calibration test ((here) that I can just differentiate RGB values of 5 and 254, thus ensuring I can fully see all highlight detail and black level detail.

willhub · 28 Feb 2018 at 09:17

I *think* I might have worked it out, only had the Samsung on and disconnected the monitor, I went into the options and deselected HDMi UHD colour for the HDMi port the pc was plugged into, this seemed to have fixed it.

Its weird how this card doesn't work with it when my old 7970 did.

bigjimmyauk · 28 Feb 2018 at 14:18

I had a similar problem to this i had to set windows to run at 59hz on hdmi through nvidia control panel if i set it to 60hz i ended up with black screen blinking issues. That's through HDMI 2.0 at 4k resolution.

my tv only has one 2.0 port and 3 1.4 ports

it's worth checking the av forums or contacting samsung directly to find out which ports are which version HDMI because it's highly unlikely they are all 2.0 due to cost and if you want to game at 4k60hz you need HDMI 2.0 or above

https://en.wikipedia.org/wiki/HDMI
good learning material on that wiki link.

willhub · 28 Feb 2018 at 18:23

My HDMi cable is rated 4k 4:4:4, 2.0 10m. Worked fine with the 7970. I have an MU6400 only has 3 HDMi ports I believe they're all 2.0

willhub · 1 Mar 2018 at 11:29

Going to try a HDMi - DP adaptor, ordered one off Amazon.

bru · 1 Mar 2018 at 12:47

willhub said:
My HDMi cable is rated 4k 4:4:4, 2.0 10m. Worked fine with the 7970. I have an MU6400 only has 3 HDMi ports I believe they're all 2.0

!0 meters that's the problem.

I ran a 15m cable around the room and it wont send a 4k signal over that distance, move the pc next to the TV, use a shorter cable and it works fine, or put up with 1080p from the PC on the TV, (which is what I've done)

I don't know of any fix for this limitation at the moment.

willhub · 1 Mar 2018 at 12:49

bru said:
!0 meters that's the problem.

I ran a 15m cable around the room and it wont send a 4k signal over that distance, move the pc next to the TV, use a shorter cable and it works fine, or put up with 1080p from the PC on the TV, (which is what I've done)

I don't know of any fix for this limitation at the moment.

I'll try a shorter cable tonight, however I've heard that the cable length shouldn't be the problem as the 10m cable was rated for 4K 4.4.4 60Hz on the rainforest.

bru · 1 Mar 2018 at 12:56

Try it and see, but from what I've tested, cable length makes much more difference than cable quality, within reason of course. ultra cheap 2m cable from the pound shop wouldn't even work.

willhub · 1 Mar 2018 at 12:59

bru said:
Try it and see, but from what I've tested, cable length makes much more difference than cable quality, within reason of course. ultra cheap 2m cable from the pound shop wouldn't even work.

Hmmm, I make sure before buying but I will try, I'll give the one a go that came with my AOC monitor.

The thing is my TV is opposite from my PC as I've had to do it that way because having the speakers near the wall annoys my next door neighbor, so I have a 10m satellite, hdmi & optical cable trailing across the floor but was the only way to do it as there is a door in the way to the balcony so can#'t have the desk on same wall as PC

Blimey, PC's eh what a nightmare.