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

[mushi]

Thank you for all your help.

The stuttering and frameskip is almost solved. I ended up using NVCP exclusively to tweak the values, since I could test it (frame skip and crosstalk) straight away and see if it was smooth, even though NVCP doesn't let me tweak the values much.
Now its almost perfect, its good enough. At first, i've managed to get good results at 239hz, but then i got good results at 240hz also. I haven't tested the limits (vertical frequency) without frameskip. ive slightly tested 242hz but with skips.

So here's what I got:
239hz

239_ok2.PNG (23.8 KiB) Viewed 235 times

and 240hz

240_ok2.PNG (23.43 KiB) Viewed 235 times

I've been tweaking the Vertical total pixels, between 1280 and 1304, for now its ok. The "problem" in NVCP is that no matter what decimal digits i put in Refresh rate (240.xxx), it always resets to .000
I might give CRU another chance though (after removing the custom resolutions in NVCP). The problem i got with CRU, I never knew which modes were actually set. thats ignorant from me, i should have seen some tutorials first. (also the OSD doesn't show actual refresh rate, it always shows either 60, 120, 144 or 240)
I wonder if this kind of overclock does any harm to the monitor in the long run. Also I wanted to know how to reset the timing settings to the monitor's defaults (I assume its the automatic option in the combobox?).

Thanks everyone, and for the ones that i saw complaining about this monitor in this thread - don't. just fiddle around a bit and it will be fine. There are good deals for this monitor if you look for them (<300 eur/usd)

[k2viper]

To reset custom resolutions and CRU settings, manually remove custom resolutions created in NVCP and use reset-all.exe from CRU bundle.

[mushi]

So, even if I had achieved success using NVCP, I wanted to try using CRU.

1st thing i did was try to replicate the settings i had success in NVCP. Curious thing, exactly the same settings on NVCP didn't produce the same result in CRU (NVCP doesnt have back porch nor blanking options though). It just wasn't smooth! I had to try others.

Now with some hours of experience, i have improved my CRU skills and reduced incertainty from my mind. I've tried the alternative VTs on k2viper's 1st post on this thread, and voilà! smooth! Incredible how a small change from the default's VT 1180 can make. I've set VT 1182 and 1184 with perfect (near perfect) results.
Here are my timings:

CRU_excelente.PNG (32.21 KiB) Viewed 205 times

very happy!
thanks k2viper!

[Chief Blur Buster]

A change of 2 made a very noticeable change? Very interesting.
If I go by the pure mathematics numbers, should have been an almost unnoticeable change.

Perhaps there was a secondary behavior change (e.g. improved overdrive formula match for the custom refresh rate match), or a large strobe-phase shift (in favour of quality).

What kind of change happened from HT2040/VT1180 -> HT2040/VT1182 -- did the "crosstalk zone move up and down" (image) to a better position or did the "crosstalk globally increase/decrease" (image) when you stared at the www.testufo.com/crosstalk motion test?

[k2viper]

So, even if I had achieved success using NVCP, I wanted to try using CRU.

1st thing i did was try to replicate the settings i had success in NVCP. Curious thing, exactly the same settings on NVCP didn't produce the same result in CRU (NVCP doesnt have back porch nor blanking options though). It just wasn't smooth! I had to try others.

Now with some hours of experience, i have improved my CRU skills and reduced incertainty from my mind. I've tried the alternative VTs on k2viper's 1st post on this thread, and voilà! smooth! Incredible how a small change from the default's VT 1180 can make. I've set VT 1182 and 1184 with perfect (near perfect) results.
Here are my timings:

CRU_excelente.PNG

very happy!
thanks k2viper!

It is not such small VT change making this huge impact on smoothness. It is the refreshrate you finally managed to get exact 239,760Hz working, exactly as mentioned in 1st post. For some reason this monitor with Nvidia GPUs is getting default 239,759 refreshrate and it isnt flawless, but 239,760 is perfect. This 239,76 number is also stated in user's manual. The workaround to fix stuttering is to get this correct refreshrate running, the easiest way to achieve it is to change VT to some pre-tested values I mentioned in 1st post.

Glad you're finally fine

[mushi]

While I agree with k2viper explanation, not all settings with perfect 239,760hz were working properly. The main recommended one of VT 1304 didn't work, even though it was 239,760hz. This may be related with my older monitor model from August 2017 and firmware 2.00. Right now, with the settings in my previous post, it's crt-like, and i'm very happy with it.

I haven't enabled MBR in any of my tests. It causes input lag, not interested. I realised later that the CrossTalk test was designed for mbr, but i used it to detect stutter in ufo's motion (which "moving photo" and "ghosting" tests did too, and maybe better/more focused). So what i was looking for in those tests was stutter.
And ofc, the ultimate test for me, is to jump around in QuakeWorld. 20+ years playing it, with 10+ years on a 160hz crt, taught me what to expect from 0 stutter, 0 input lag. And the settings on my previous post (CRU) are it (in my case!). On a side note, with the settings I had with NVCP before, which I classified as "near perfect", the testUfo tests showed no problem - i couldn't find an issue, just a very slight stutter in the moving ufo tests - but I knew they weren't perfect when i tested them on QuakeWorld. So i knew i had to continue investigating, and finally got it with cru.
Did i say already im very happy?

Finally, i'm sorry to have made a couple of alarming posts without using the required testing methodology. I was quite sad when i realised that the recommended settings didn't work with my monitor. Since, I've learned alot about monitors in general. I'm not an english native, and many of the terms you experts talk about here were unknown to me (as i never needed to fiddle around with them). but in the end, it all turned out great!
kudus and much respect to all the experts in this forum (in which i've lurked since its inception!) keep the great job going!

ps. The last time i've learned about monitors, was about the relation of horizontal frequency with vertical frequency. The formula to find the max vertical frequency (at least in crt monitors) is: VerticalHz = ((MaxHorizontalkHz*1000)/HorizontalLines) * 0.95 I wish i knew this back in 1998 - would have saved alot of work

[captain_amn]

While I agree with k2viper explanation, not all settings with perfect 239,760hz were working properly. The main recommended one of VT 1304 didn't work, even though it was 239,760hz. This may be related with my older monitor model from August 2017 and firmware 2.00. Right now, with the settings in my previous post, it's crt-like, and i'm very happy with it.

I haven't enabled MBR in any of my tests. It causes input lag, not interested. I realised later that the CrossTalk test was designed for mbr, but i used it to detect stutter in ufo's motion (which "moving photo" and "ghosting" tests did too, and maybe better/more focused). So what i was looking for in those tests was stutter.
And ofc, the ultimate test for me, is to jump around in QuakeWorld. 20+ years playing it, with 10+ years on a 160hz crt, taught me what to expect from 0 stutter, 0 input lag. And the settings on my previous post (CRU) are it (in my case!). On a side note, with the settings I had with NVCP before, which I classified as "near perfect", the testUfo tests showed no problem - i couldn't find an issue, just a very slight stutter in the moving ufo tests - but I knew they weren't perfect when i tested them on QuakeWorld. So i knew i had to continue investigating, and finally got it with cru.
Did i say already im very happy?

Finally, i'm sorry to have made a couple of alarming posts without using the required testing methodology. I was quite sad when i realised that the recommended settings didn't work with my monitor. Since, I've learned alot about monitors in general. I'm not an english native, and many of the terms you experts talk about here were unknown to me (as i never needed to fiddle around with them). but in the end, it all turned out great!
kudus and much respect to all the experts in this forum (in which i've lurked since its inception!) keep the great job going!

ps. The last time i've learned about monitors, was about the relation of horizontal frequency with vertical frequency. The formula to find the max vertical frequency (at least in crt monitors) is: VerticalHz = ((MaxHorizontalkHz*1000)/HorizontalLines) * 0.95 I wish i knew this back in 1998 - would have saved alot of work

If im not mistaken, MBR wil not affect the input lag noticeably, so please test it with MBR on, i am still interested in buying this LG monitor cause the Alienware 240hz is still not back in stock.

This would help me greatly, if you could test quake with mbr enabled, thank you!

[mushi]

And you're right.
I've tried it ofc. You playing QC? you won't notice it.

[Kheri]

And you're right.
I've tried it ofc. You playing QC? you won't notice it.

Even if the MBR is kinda bad, you should notice it in-game, IMO. So that's interesting! 240fps?

[mushi]

i've tested MBR more extensively.
in fast 3rd person shooters, the difference is noticiable, at least for me. On the other hand, I've seen people say it improves the visibility on tracking weapons, and i can confirm it.
In the end of the day, its a matter of preference. I liked MBR on and will definetely enable it in some games, even in some fps. For Quake, i will leave it off - for now. TFTCentral says its the best implementation they've seen, its indeed nice.