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

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

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

Post by addi » 02 Feb 2019, 12:46

mushi wrote:So I bought a 27GK750F and I guess I had bad luck. Because 240hz has stutter, and what it seems frame skipping.
I have tried several CRU settings, without luck. on 144hz it works fine, no stutter.

I've shared a folder with pictures and videos, take a peek.
https://drive.google.com/open?id=1rkmAD ... jKdGB1siHv

Facts:
* The issue is more noticiable on FPS games, like Quake.
* I have more than 240 fps on those games
* I have a 960gtx, so freesync will not work
* enabling vsync doesnt make a difference in the stuttering. but its bad for fps, so doesn't matter
* I've tried the recommended CRU settings on the first post, and other posts aswell .
* I've tried HDMI and DP
* mouse is running at 1000hz
* My previous monitor was an old 120hz one, no issues (and high end CRTs before)

Questions:
* my firmware doesn't have FASTER response time option. why?
* I've tried to create different refreshe rates on CRU, always gives me black screen. Any tips? I didn't mess around much with the different options.
* how to create different refresh rates? without black screen?
* never messed around with the "extension block" menu before this. should i?..

My current CRU settings for 240hz are okay-ish. 144hz is still much smoother.
I would appreciate some help.
Same here... I played around with some custom timings and it worked pretty well.
I can share my settings, after a bit more of testing.


I feel like i might contact LG about that, cause it's anoying as hell... The Monitor is basicly unusable out of the box @ 240 Hz.

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

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

Post by mushi » 02 Feb 2019, 14:31

please do share. and tell me how do you figure out the values to try. thanks!

Kheri
Posts: 59
Joined: 29 Sep 2018, 13:39

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

Post by Kheri » 02 Feb 2019, 15:32

mushi wrote:please do share. and tell me how do you figure out the values to try. thanks!
I would just return it. Seriously. Which version do you have, btw?

Edit: Oh, version 2.00, I guess

Mine's version 3.07 (and it still has a bad strobing implementation).

<blank>
Posts: 9
Joined: 01 Feb 2019, 12:30

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

Post by <blank> » 02 Feb 2019, 17:09

addi wrote:
mushi wrote: * I have a 960gtx, so freesync will not work
Could it be an issue of older maxwell cards or is it the monitor? Cause i have gtx 970 g1 myself. dp 1.2 can push 1080p 240hz but not adaptive sync, which is dp 1.2a and onwards. I dont mind as ill be making sure fps stays at or close to 240fps anyway. From all the comments gathered here i cba to mess around with settings so i'll just pick up the alienware one and call it quits. Just a matter of luck getting a decent panel. The shop im eyeing is going to order new stock so i hope they actually get one of the latest models and not some old stuff that sat in the warehouse since they were first made.

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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 » 03 Feb 2019, 05:10

Guys, please read TLDR post (FAQ) at the thread start.
Stuttering is known issue and it has a solution.

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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 » 03 Feb 2019, 05:12

Kheri wrote: Mine's version 3.07 (and it still has a bad strobing implementation).
Whats wrong with the strobing implementation on your unit?

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

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

Post by mushi » 03 Feb 2019, 06:53

k2viper wrote:Guys, please read TLDR post (FAQ) at the thread start.
Stuttering is known issue and it has a solution.
I've read 90% of the thread. The suggested settings in CRU are a massive improvement over the original settings (i've tested using the "compare frame rates" testufo and my favorite fps games).
But microstutters are still visible at 240hz, not so much in testufo, but in fast fps games. And are a deal-breaker. See the video i shared in my previous post.
144hz gives me the best experience. I haven't tried tweaking the values yet (as its not crt-like yet) because i don't know how.
anyone interested in further testing? as it is, its not good enough. at this point my 9 year old 120hz lg has less issues.

my firmware is 2.00, old. is there any way to upgrade?...

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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 » 03 Feb 2019, 08:58

What is production date (label on the back)? Never seen 2.00 fw before, and also I havent seen "Tool option 2-3-4-5" in my 3.06 fw service menu. What are their contents?

And it looks like you did wrong with CRU.
240hz resolution under Extension blocks is the one you need to modify. You have to make it exact 239,760Hz Actual refresh rate as it stated in TLDR. You dont need to create/modify ANY resolutions under Detailed resolutions block, only under Extension blocks. Your 240.763hz resolution is wrong and if it even works, it will likely frameskip/stutter.
On your CRU screenshot there is the right resolution with 577,15Mhz pixelclock, it is the one you need to make exact 239,760Hz. Remove resolutions you created under Detailed resolutions and tweak the one under Extension blocks.

Make sure you use CRU right next time :)

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

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

Post by mushi » 03 Feb 2019, 10:11

Thanks on your insights on cru - but that doesn't solve the issue. (i've updated the cru image on the shared folder).
its August 2017. the contents of the service menu are on the shared folder.
Any way to update the firmware? how to improve even further your findings?
thx

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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 » 03 Feb 2019, 11:12

You still get stuttering and unsmoothness with VT1304 239,760Hz resolution?

Are you sure that this CRU resolution on your screenshot is the only 240Hz resolution you have under Standard resolutions, Detailed resolutions, and Extension blocks? There should be no duplicates. Also remove any custom resolutions you may have created via Nvidia control panel.

VT1304, VT1182, VT1184 with actual 239,760 refresh rate should be non-issue if it actually enabled and works. I suppose you messed up something while creating many duplicated resolutions under wrong CRU sections.
I uploaded a .bin CRU file for you, with correct VT1304 resolution and no duplicates. Use CRU reset-all.exe before importing.

https://dropmefiles.com/fU9Dj

I dont know any ways to update firmware yet (and no sources of newer firmware too).

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