LG 27GP950 causing issues

[SADS]

Not sure if anyone is able to shed any light on this...

I just got a GP950 (lucky me!) and i run dual monitors, my second screen is an older XB270HU and i use a 1080Ti, both screens connected via displayport.

 

My issue is that if the GP950 turns off, when it turns back on again.. it crashes my system.

This only happens if running it at 4k/120hz.

 

The screen by default goes up to 4k/95hz as selectable, I had to create a custom resolution to enable it to run 4k/120hz.

But this is really annoying as if I am away from my machine or lock the screens, they go into standby and eventually turn off. When I try to resume the machine it crashes.

Obviously I want to be able to run my machine at 4k/120hz at all times, but it seems like if I want to avoid the crashing, I have to dip back down to 4k/95hz (first world problems i know).

 

I've tried (just bought) new cables for the screens as well as run the firmware updater for the 1080Ti, neither seem to have had an effect.

[Stahlmann]

What color depth do you have selected? 4K 120Hz will only work with 8bit because you don't have a DP 1.4 DSC capable GPU.

4K 10bit only goes up to 98Hz.

[SADS]

NV control panel looks like its at:

32bit desktop colour depth

8bpc output colour depth

RGB output colour format

Full output dynamic range.

[Stahlmann]

1 hour ago, SADS said:

NV control panel looks like its at:

32bit desktop colour depth

8bpc output colour depth

RGB output colour format

Full output dynamic range.

Please remember to quote people so we can see that you replied.

 

Everything looks as it should be...

Just to confirm, at 95Hz everything is fine?

 

Did you check if there is a new firmware for your monitor?

 

Did you try the cable that was included with the monitor?

 

Do you already have the newest GPU driver? (471.11  WHQL)

[SADS]

4 minutes ago, Stahlmann said:

Please remember to quote people so we can see that you replied.

 

Everything looks as it should be...

Just to confirm, at 95Hz everything is fine?

 

Did you check if there is a new firmware for your monitor?

 

Did you try the cable that was included with the monitor?

 

Do you already have the newest GPU driver? (471.11  WHQL)

Ah my bad!

 

Yep at 95Hz everything seems to be ok, i can plug it in/out turn it on/off and its fine.

 

I will have a look for new monitor firmware, but its brand new. I think that there's even very little info on the LG site about it.

 

I had tried the cable that came with the monitor first. I had read about people with the previous model of this monitor (GN950) having issues with the supplied cable, so I ordered new cables to check that it wasn't anything similar.

 

I thought i downloaded the latest drivers yesterday and installed 466.77... seems somethings not right there because i can now see 471.11 as you mention. will update that now too!

 

feedback to follow

appreciate the input!

[Stahlmann]

20 minutes ago, SADS said:

I will have a look for new monitor firmware, but its brand new. I think that there's even very little info on the LG site about it.

You need the LG "On Screen control" software. Through that you can update your firmware (as long as you plugged in the USB cable between the monitor and PC). With new models it happens pretty frequently that they find problems after the monitor is available to the public.

 

20 minutes ago, SADS said:

I had tried the cable that came with the monitor first. I had read about people with the previous model of this monitor (GN950) having issues with the supplied cable, so I ordered new cables to check that it wasn't anything similar.

When i still had my 27GN950, i only used the supplied cable. For me it worked @ 4K 144Hz 10bit. Of couse i had a DSC capable GPU to achieve that.

 

[SADS]

1 minute ago, Stahlmann said:

You need the LG OSD software. Through that you can update your firmware. With new models it happens pretty frequently that they only find problems after the monitor is available to the public.

 

When i still had my 27GN950, i only used the supplied cable. For me it worked @ 4K 144Hz 10bit. Of couse i had a DSC capable GPU to achieve that.

 

Ok, I've updated the drivers and installed the OSD, it seems that there are no new updates flagging up at the moment and I'm still getting the same issue.

 

It's so strange. It's like the system crashes when it tries to turn on the screen at 120hz.

It's gotten a little worse now too. My system wont even boot up properly with the screen set to that mode, I have to unplug it and clean the connection and configuration entries from the registry to be able to boot up properly again.

[Stahlmann]

21 minutes ago, SADS said:

Ok, I've updated the drivers and installed the OSD, it seems that there are no new updates flagging up at the moment and I'm still getting the same issue.

 

It's so strange. It's like the system crashes when it tries to turn on the screen at 120hz.

It's gotten a little worse now too. My system wont even boot up properly with the screen set to that mode, I have to unplug it and clean the connection and configuration entries from the registry to be able to boot up properly again.

That seems more like a driver / GPU incompatibility issue to me than anything else. Strange...

 

Do you have any chance to see if it works on another GPU? Maybe take it to a friend for testing? That would at least rule out that the monitor is the problem.

[SADS]

10 minutes ago, Stahlmann said:

That seems more like a driver / GPU incompatibility issue to me than anything else. Strange...

 

Do you have any chance to see if it works on another GPU? Maybe take it to a friend for testing?

I might be able to find an old GPU that I could try it out on instead.

I don't think I know anyone locally with anything newer than me

 

It does seem that the system is getting confused between the screens a bit though. Even when idle for a few mins and the screens go off. it seems to want to shift all the windows onto one screen.

I think that its having problems with the screen going full on/off and the displayport connection going online/offline rather than going into some sort of standby mode.

[Stahlmann]

1 hour ago, SADS said:

I don't think I know anyone locally with anything newer than me

It doesn't have to be something newer. Just another GPU with DP 1.4. If you have the same behavior there, it's the monitors fault. If there is no problem there, it's your hardware.

[SADS]

4 minutes ago, Stahlmann said:

It doesn't have to be something newer. Just another GPU with DP 1.4. If you have the same behavior there, it's the monitors fault. If there is no problem there, it's your hardware.

I think I might have it figured out.

 

In the monitors settings, you can chose if you want to use DP1.2, DP1.4 or DP1.4(dsc).

 

I've changed it from DP1.4(dsc) down to DP1.4 and im testing out now to see if i causes and problems still.

One positive thing so far, is that the 4k/120hz option is appearing now without the need for a custom resolution profile.... So I am keeping my fingers crossed and doing some tests now to confirm if this has sorted it.

[Stahlmann]

40 minutes ago, SADS said:

I think I might have it figured out.

 

In the monitors settings, you can chose if you want to use DP1.2, DP1.4 or DP1.4(dsc).

 

I've changed it from DP1.4(dsc) down to DP1.4 and im testing out now to see if i causes and problems still.

One positive thing so far, is that the 4k/120hz option is appearing now without the need for a custom resolution profile.... So I am keeping my fingers crossed and doing some tests now to confirm if this has sorted it.

Totally forgot about that setting. Yeah that could be the problem.

[SADS]

To update:

So far so good!

If you have this monitor and are running a non-DSC graphics card, then you'll probably need to adjust the screen via the OSD down to the correct DisplayPort version.

 

Now I've got to sort out Windows moving all the windows to the primary screen after unlocking