Blur Busters Forums

Who you gonna call? The Blur Busters! For Everything Better Than 60Hz™ Skip to content

G-sync Causing Weird Checkerboard-like Pixelation on screen

Talk about NVIDIA G-SYNC, a variable refresh rate (VRR) technology. G-SYNC eliminates stutters, tearing, and reduces input lag. List of G-SYNC Monitors.

Re: G-sync Causing Weird Checkerboard-like Pixelation on scr

Postby Aeon » 30 Jul 2017, 11:11

Chief Blur Buster wrote:if GSYNC 120fps@120Hz looks worse than normal 120fps@120Hz

just tested it in cs:go. 120fps@120hz with or without g-sync looks 100% identical, no artifacts at all.

Well, thanks you all for answers. I think I can live with that without problem. <60fps is a shitty experience anyway
Aeon
 
Posts: 5
Joined: 28 Jul 2017, 14:50

Re: G-sync Causing Weird Checkerboard-like Pixelation on scr

Postby Chief Blur Buster » 30 Jul 2017, 17:27

Aeon wrote:
Chief Blur Buster wrote:if GSYNC 120fps@120Hz looks worse than normal 120fps@120Hz

just tested it in cs:go. 120fps@120hz with or without g-sync looks 100% identical, no artifacts at all.

Well, thanks you all for answers. I think I can live with that without problem. <60fps is a shitty experience anyway

Ok, we ruled out a certain type of inversion defect, then!
If you see no inversion artifact difference between GSYNC and non-GSYNC at stable and high frame rates.

So, it appears that it is simply the varying of your refresh rate that's amplifying inversion artifacts.

This is a common problem on many VRR monitors, especially of the TN type.

That said, some TN panels do a much better job, so if you buy a different TN GSYNC monitor, you might (or might not) have far less inversion artifacts during variable situations.

If you want a monitor that doesn't have VRR-induced visibility of inversion artifacts, you may want to consider an IPS GSYNC monitor. There are pros/cons if you go this approach (Slower pixel response) but it's an option if you're heavily annoyed by inversion artifacts.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
To support Blur Busters: Official List of Best Gaming Monitors | G-SYNC | FreeSync | Ultrawide
User avatar
Chief Blur Buster
Site Admin
 
Posts: 3759
Joined: 05 Dec 2013, 15:44

Re: G-sync Causing Weird Checkerboard-like Pixelation on scr

Postby lexlazootin » 31 Jul 2017, 07:47

Can i ask why no one thinks this is FRC? I've have a 144hz G-Sync and have the same problem as this guy, when the framerate drops low enough you can see the dithering taking place, when you reach 50fps~ or whatever the FRC simply stops. I'm guessing because of the FPS doubling in G-Sync.

I'm thinking that maybe this is just due to the inefficient way they coded it in the G-Sync chip at the time.
lexlazootin
 
Posts: 968
Joined: 16 Dec 2014, 02:57

Re: G-sync Causing Weird Checkerboard-like Pixelation on scr

Postby jorimt » 31 Jul 2017, 10:38

@lexazootin,

I'm no expert on FRC, but I'd assume that it is a constant, passive process. The dithering may be more apparent with certain colors or color combinations (gradients, non-primaries, etc), but I'm not sure FRC would be so obviously affected by framerate or refresh rate.

Also, again, G-SYNC panels have quality standards, and 144Hz G-SYNC displays are almost always capable of a complete 30-144Hz range. The minimum refresh range (FPS doubling) usually only starts at 36Hz/FPS because it is the lowest direct divisible (without going below 30Hz) of 144Hz, so I don't think that is the cause either.

You're likely just seeing pixel inversion artifacts at lower refresh rates (where, as we've already stated, they would be exacerbated).
Blur Busters Contributor - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
To support Blur Busters: Official List of Best Gaming Monitors | G-SYNC | FreeSync | Ultrawide
User avatar
jorimt
 
Posts: 406
Joined: 04 Nov 2016, 10:44

Re: G-sync Causing Weird Checkerboard-like Pixelation on scr

Postby Chief Blur Buster » 31 Jul 2017, 10:56

On some displays I've seen, FRC artifacts shows up as a random-noise dithering pattern on dark shades at lower refresh rates. And inversion aritifacts shows up as a regular pattern (e.g. fine checkerboard patterns, or horizontal/vertical lines). FRC is essentially temporal dithering, and that is more visible at lower refresh rates.

Usually, only one or the other is visible, but occasionally, on some displays, both can interact with each other to create an amplified artifact that's not visible with FRC only or inversion only. A superimposition of random noise (snow) and regular patterns. It doesn't always happen but it has happened before.

Inversion artifacts from imperfect inversion: If you see a checkerboard or regular pattern (horizontal lines or vertical lines), you are probably witnessing LCD inversion. These patterns may flicker erratically during udulations in refresh rate during VRR operation, especially at lower refresh rates.

FRC artifacts from FRC temporal dithering: The best FRC implementations use random-noise dithering (like DLP/plasma does) which has minimal interactions with inversion. If you see stationary-noise or random-noise (faint "analog TV snow" in dark greys at lower VRR refresh rates), you are probably witnessing FRC. FRC could also be ordered dithering patterns too, which would have more interaction problems with inversion artifacts. If they chose a very poor FRC pattern (e.g. ordered dither patterns), the two combined (FRC pattern + inversion pattern) can amplify the visibility of artifacts.

Ideally FRC and inversion logic should be completely invisible to human eye, but isn't always...
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
To support Blur Busters: Official List of Best Gaming Monitors | G-SYNC | FreeSync | Ultrawide
User avatar
Chief Blur Buster
Site Admin
 
Posts: 3759
Joined: 05 Dec 2013, 15:44

Previous

Return to G-SYNC

Who is online

Users browsing this forum: No registered users and 6 guests