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

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

Post by Chief Blur Buster » 05 Dec 2018, 12:41

VT tricks can be extremely subtle in reducing strobe crosstalk.
This is what should happen with http://www.testufo.com/crosstalk animation test pattern while tweaking vertical totals.

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(Example for 120Hz blur reduction.... crosstalk patterns/spacings is often worse/different at 240Hz.... but it illustrates why we do Vertical Total tweaking, larger blanking intervals at the same Hz, always is better for motion blur reducing modes.)

Small increases in VT may only widen the clear zone by a few pixels taller.
Huge increases in VT are required to get very noticeable crosstalk zone thinnings.

(Yeah.... The art of "cramming LCD GtG into VBI" for strobe backlights.... made human-eye visible by TestUFO Crosstalk during strobe tuning.)
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k2viper
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Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by k2viper » 06 Dec 2018, 08:49

Thank you Chief, a perfect illustration of what to expect out of VT tweaking!

Kheri, yes I'm talking that ~1580 VT ceiling isnt due to pixelclock limits, since LG is capable of 640Mhz. It's probably a Mstar firmware limitation for 1080p, as this limit is the same for 120 and 144 and I tried 180hz.

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

Post by Kheri » 06 Dec 2018, 10:07

The best I can manage are blurry/unfocused pics. Wish my camera would focus, it'd really help to have the pics, they just seem useless this blurry.
I went ahead and tried to look for even the minutest changes, and looked at the top and bottom of the screen.. maybe I haven't found the right area to check. But it's clear to me there probably isn't any change (at 120hz with different vtotals the change should be obvious - it's obvious in k2viper's pics.) So, is there any reason why there wouldn't be any change? Drivers? Software? GPU? Version? Etc. What could I do?

Yeah, noticed the limitation wasn't based on the pixelcock, as well. Too bad, I suppose. :/

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

Post by k2viper » 09 Dec 2018, 08:45

Another way you may try to kick VT tweak in, is Nvidia control panel custom resolution, if CRU doesnt work for you (btw make sure you start CRU with admin privileges).

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

Post by Gregix » 17 Dec 2018, 14:06

Well, just ordered it from amazon.de. Hope I will be satisfied with it, as I was with my Benq XL2720Z after VT tweak and some blurbusters utility set up.
Probably will have it after Christmas anyway, but what cable is recommended? DP or HDMI?
[email protected], 2080s, ddr4 4100c15, sb ae-7 plus ATH M50XBT. Screen VS Elite XG270, had XL2546, XL2720Z, LG 27GK750F-B, Dell 2412M...

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

Post by XAKE » 18 Dec 2018, 22:42

Gregix wrote:Well, just ordered it from amazon.de. Hope I will be satisfied with it, as I was with my Benq XL2720Z after VT tweak and some blurbusters utility set up.
Probably will have it after Christmas anyway, but what cable is recommended? DP or HDMI?
It is necessary to use only DP, HDMI does not support 240hz

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

Post by Chief Blur Buster » 19 Dec 2018, 00:29

XAKE wrote:
Gregix wrote:Well, just ordered it from amazon.de. Hope I will be satisfied with it, as I was with my Benq XL2720Z after VT tweak and some blurbusters utility set up.
Probably will have it after Christmas anyway, but what cable is recommended? DP or HDMI?
It is necessary to use only DP, HDMI does not support 240hz
It depends on HDMI standard.

I'm using 240Hz via HDMI from my ViewSonic XG2350

HDMI has no refresh rate restriction, but standardization needs to permit the bandwidth of 240Hz
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Re: LG 27GK750F-B - 240Hz, 27" 1ms Blur reduction, Freesync

Post by XAKE » 19 Dec 2018, 01:28

Chief Blur Buster wrote:
XAKE wrote:
Gregix wrote:Well, just ordered it from amazon.de. Hope I will be satisfied with it, as I was with my Benq XL2720Z after VT tweak and some blurbusters utility set up.
Probably will have it after Christmas anyway, but what cable is recommended? DP or HDMI?
It is necessary to use only DP, HDMI does not support 240hz
It depends on HDMI standard.

I'm using 240Hz via HDMI from my ViewSonic XG2350

HDMI has no refresh rate restriction, but standardization needs to permit the bandwidth of 240Hz
I agree. But specification of this monitor does not allow to use 240hz in HDMI mode

PS
I studied the instructions, yet the monitor with hdmi 2.0 supports 240hz, strangely, but I did not succeed in HDMI more than 144hz , my GPU GTX 1080

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

Post by k2viper » 19 Dec 2018, 12:28

It was reported that over HDMI it does not work with high VT's as over DP, so Displayport is recommended.

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

Post by Chief Blur Buster » 19 Dec 2018, 14:40

Thanks for the report!
HDMI protocol technically supports large VTs but not all HDMI transceiver chips like them.

It works best when the HDMI chip supports FreeSync, because FreeSync-compatible connections are usually the most Large-VT-friendly connections.
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Forum Rules wrote:  1. Rule #1: Be Nice. This is published forum rule #1. Even To Newbies & People You Disagree With!
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