LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

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mushi
Posts: 32
Joined: 02 Feb 2019, 11:46

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by mushi » 13 May 2019, 10:21

aJam wrote:I got the LG, set up as advised
What is the firmware version? What VT are you using? Tested the testufo frameskip test?
Congrats btw. ;)

addi
Posts: 16
Joined: 02 Feb 2019, 12:42

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by addi » 22 May 2019, 04:50

It's a shame that LG still haven't gave us any update for the issue we forwarded to them.
I had high hopes when they replied to the post on the LG forum.

But now, it seems like they just let this whole thing die down.
A pity...

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witega
Posts: 49
Joined: 08 Jun 2019, 11:40

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by witega » 08 Jun 2019, 12:10

Greetings folks,

I registered on this site to help out some folks who are encountering stuttering or artifact issues using CRU with the settings by k2viper in the original post. This issue may be exclusive to 20 series Nvidia RTX cards, but I think the problem lies in the CRU program itself.

First of all, I want to thank k2viper for all his work on getting the best settings out of this monitor and achieving a near 240hz refresh rate in CRU. Thank you so very much. I also want to thank Mark Rejhon for hosting this site and providing invaluable information regarding blur reduction, recommended monitors, testing and etc. I've used this site over the years and it has been tremendously helpful. Major kudos to you Mark and thanks!

Ok so onto the LG 27GK750F-B monitor and reports of those still encountering stuttering or artifact issues using CRU. I believe I have discovered the root cause of folks still having issues after changing the settings in CRU to match what k2viper has in the OP.

The cause is sometimes CRU is not applying the settings properly to the graphics driver itself.

What this means is you may need to restart the driver (using the restart.exe provided by CRU) and possibly go into Recovery Mode after restarting the driver to ensure the settings are in effect.

In order to test this, I would recommend running a benchmark test. Let's use Unigine Heaven as an example. I would have G-Sync enabled and use the optimal settings user "jorimt" shows here: https://www.blurbusters.com/gsync/gsync ... ttings/14/

When you run the Heaven benchmark test, if your framerate is capped at 120FPS then the settings in CRU are NOT working. You will also see black line artifacts as show in this video I uploaded below:

RTX2080Ti artifacting Unigine heaven benchmark
https://www.youtube.com/watch?v=PNmefTkyVdg

You will need to restart the driver, run the benchmark again to test. If it still is capped at 120FPS, you will need to restart the driver and then go into Recovery Mode which should fix the issue. (For me going into Recovery Mode fixes my problems 100% of the time). Now running the Heaven benchmark you should have the framerate uncapped and it'll go higher than 120FPS depending on the card you use.

Another way to test this is to use a game that has a poorly optimized game engine, I've chosen PUBG. After you click "Play" in Steam under PUBG, if the resolution switches to a much lower setting upon start up then reverts to 1080p in the Menu...once again the settings in CRU are NOT working. You can tell the lower resolution because the Steam notification and PUBG logo will appear in the top left hand corner in stretched magnified way. Almost looks like it dips down to 256x224 resolution before going back to 1920x1080. Again follow the steps above to restart the driver and then when launching the game it will no longer start at a low resolution but stay in 1080p.

Also you will know CRU is not working because it will introduce these kind of black line artifacts in PUBG:

PUBG artifacting RTX2080ti #1
https://www.youtube.com/watch?v=5NLg_wd1mWM

PUBG artifacting RTX2080ti #2
https://www.youtube.com/watch?v=usw2L6OuFH8

And you will also experience stuttering in game.

If your card can output more frames than 240 for games like Rocket League and CS:GO, but you can see/feel stuttering...then CRU settings are not working. You should not experience any kind of stuttering or artifacts in both those games if the driver with CRU settings is working correctly.

Conclusion: It may take multiple restarts using the restart.exe CRU provides to get the settings applied to the Nvidia graphics driver. After I boot up my PC, I usually run the restart.exe and then go into Recovery Mode as a double check. Then I run a benchmark program after to make sure the driver with CRU settings are working.

Your monitor may continually turn off and on after restarting the driver. You'll need to get into the OSD, power off the monitor, leave it off for a minute or two, turn it back on, then restart the drivers again.

I know it sounds like a pain and truly this is completely unacceptable that LG sells a monitor with this much hassle and you have to use a 3rd party software program to get near 240hz. But I will say it is a much better panel than my BenQ 144hz one was at colors.

When I encountered the stuttering and the black line artifacts, I thought it was my graphics card having problems but when I ran a video capturing program while running the Heaven benchmark, it wouldn't pick up on those lines. So then I thought perhaps it was the monitor, which led me down to restarting CRU a few times and the issue was resolved. I'm thankful I don't have to RMA either the monitor or card...at least not yet.

Thought this post might be helpful to some folks who are frustrated with stuttering/artifacts even after following the instructions in k2viper's OP.

Let me know if there are any questions to the above and I can try to answer.

Again thank you so much for this thread and website.

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witega
Posts: 49
Joined: 08 Jun 2019, 11:40

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by witega » 09 Jun 2019, 21:18

Apologies for the duplicate post, but I wanted to experiment a bit turning Freesync off (and thereby having G-Sync off) and turning on MBR in the OSD. These are the identical settings found in k2viper's OP.

I had some difficulty getting the driver's to restart with CRU's settings enabled. I still detected stuttering in a high-FPS game like CS:GO and also saw the black line artifacting as I posted earlier. Running the Heaven benchmark, while the FPS was uncapped, still exhibited this artifacting behavior. Clearly the driver was not restarted correctly.

It took multiple restarts from CRU's own "restart.exe" and going into Recovery Mode to finally having the CRU settings applied to the Nvidia driver. No more stuttering or artifacts. I also noticed the power button light under the monitor panel is off, which if I'm not mistaken usually is on when the monitor is powered. A bit bizarre.

Anyway it seems the monitor and graphics driver are a bit finicky with each other, which requires multiple resets to finally have the monitor operate as it should.

So for those that still can't get stuttering-free gameplay and possibly artifacting, keep restarting the drivers until it works.

Also it seems to me that the monitor no longer power cycles every 2 seconds once the driver has been correctly restarted. My monitor would exhibit behavior of turning off and back on again whenever I used the CRU "resetart.exe" application, when the settings were not enabled. But whenever I get the driver working with the CRU settings, my monitor doesn't do this power on/off behavior. This is something I will continue to track in the coming weeks.

buratino0611
Posts: 3
Joined: 15 Jun 2018, 01:54

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by buratino0611 » 21 Jun 2019, 06:08

My current BenQ 2720z broke the Panel so...
I just buy a new LG one today for enjoying OverWatch
So can anyone update the latest setting of this LG monitor for optimizing the lowest input lag plz ?
including: menu settings and the CRU

Hopefully, this LG 240hz have a better show since i tried the LG 24GM77 on Motion 240 mode 5 yrs ago :D

CrosShadow
Posts: 1
Joined: 28 Jun 2019, 09:21

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by CrosShadow » 28 Jun 2019, 10:42

So, i recently bought 2 of these screens and i seem to have troubles over troubles, hoping i can find some sort of help from you guys...
So here's my problem, the first one i bought had burnt sub pixels but everything else was fine, so i tried the luck with another sample which turned to be perfect on that aspect BUT has another weird problem i never have seen before which appears to be happening at 120p/s and 240p/s... This issue isn't present on the previous panel with burnt subpixels.
It's clearly visible ingame when moving the camera not too fast, i messed with overdrive and all the settings but it doesn't really improve anything, only sharpness makes it a lil less visible.
It's hard to get it on camera, i posted a picture but i'll try to describe it too, it looks like there's a grid when moving the camera ingame and it has the same effect on the ufo tests etc on 120 and 240p/s, it doesn't show that much in higher speeds, again switching between the 2 panels and i can definitely tell that the other panel doesn't have this issue, both have 3.08 firmware.

https://imgur.com/zo5uiMh

Ok, took for reference 2 pictures pursuiting by hand with the same settings of both screens at 120p/s of the tower, those are the results...
https://imgur.com/a/wp4QPOM Here's a better comparison about what i am talking about.

Any suggestion is welcome, i really don't want to try the luck with a 3rd screen...

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k2viper
Posts: 293
Joined: 23 Jan 2018, 06:30

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by k2viper » 04 Jul 2019, 04:57

witega wrote: Also it seems to me that the monitor no longer power cycles every 2 seconds once the driver has been correctly restarted. My monitor would exhibit behavior of turning off and back on again whenever I used the CRU "resetart.exe" application, when the settings were not enabled. But whenever I get the driver working with the CRU settings, my monitor doesn't do this power on/off behavior. This is something I will continue to track in the coming weeks.
In my experience, turning off and back on behavior of the monitor is barely caused by incorrect Nvidia driver behavior. First - even if monitor is "blackscreening", the picture is still smooth and no stuttering (when it shows picture). Second, powercycling the monitor completely fixes blackscreeening for a time regarding how often do you open OSD (im my case it is between days and weeks of stable operation). These are clearly a monitors' firmware bugs imo, not an Nvidia driver's fault.

Thanks for your experience and helpful things shared, you may also give a shot of starting CRU.exe and restart.exe with administrator rights.
Last edited by k2viper on 04 Jul 2019, 05:06, edited 1 time in total.

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k2viper
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Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by k2viper » 04 Jul 2019, 04:59

buratino0611 wrote: So can anyone update the latest setting of this LG monitor for optimizing the lowest input lag plz ?
including: menu settings and the CRU
Optimal settings are described in first post. In short, make sure you connect it via DP cable and choose "Original" scaling mode (Исходный in Russlan)

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k2viper
Posts: 293
Joined: 23 Jan 2018, 06:30

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by k2viper » 04 Jul 2019, 05:04

CrosShadow wrote: It's hard to get it on camera, i posted a picture but i'll try to describe it too, it looks like there's a grid when moving the camera ingame and it has the same effect on the ufo tests etc on 120 and 240p/s, it doesn't show that much in higher speeds, again switching between the 2 panels and i can definitely tell that the other panel doesn't have this issue, both have 3.08 firmware.

https://imgur.com/zo5uiMh

Ok, took for reference 2 pictures pursuiting by hand with the same settings of both screens at 120p/s of the tower, those are the results...
https://imgur.com/a/wp4QPOM Here's a better comparison about what i am talking about.

Any suggestion is welcome, i really don't want to try the luck with a 3rd screen...
Pixel inversion artifacts (grid), are afair found on many panels that are B-grade in terms of quality. It is the exact piece of panel fault, but I'm not sure whether you can RMA it for that reason. Contact your seller. Not all units have this, as you may see by yourself, but I know no real workaround to fix it - besides make it less visible via contrast/gamma tuning.

BrokeChemGrad
Posts: 5
Joined: 08 Jul 2019, 18:36

Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by BrokeChemGrad » 08 Jul 2019, 18:51

I have a question for you. I got this monitor about a month ago, and it is ok. I recently came from a OMEN 25 144hz and that one wasn't too bad. My problem with this monitor and I'm not sure if it is me or the product, but it seems very hard to focus. I played CRT back in the day, and I know the motion blur reduction tech just inserts black frames every frame to trick you into a more smooth motion, but my games don't seem smooth to me. I'm running a RTX 2080 which also has its fair share of problems from what I read. Games seem a little washed out compared to my 60hz ASUS 1080p monitor next to it. I tried your custom res fix k2viper and I'm not sure if I am supposed to notice any differences or not. Is it a problem mixing my 60hz with my 240hz monitor? Any feedback is welcome.

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