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
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
PUBG artifacting RTX2080ti #2
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.