G-SYNC Brightness Flickering!

[KeyS]

Hello everyone,

Recently my EVGA 1080Ti FTW3 died and I have switched to a EVGA 2080Ti FTW3 Ultra but have been having a really annoying issue.

With the 1080Ti I used DVI for 144hz - everything was great.

With the 2080Ti there are no DVI ports so I've had to switch to Display Port.

Now, with the Display Port my monitor (BenQ XL2420G) only allows the G-SYNC engine to be selected, G-SYNC can still be disabled via NVCP but there are still issues even with it being disabled.

First issue, with G-SYNC ON (fullscreen or fullscreen / windowed) there is obvious "brightness flickering" on the desktop and within games which is incredibly annoying.

Second issue, with G-SYNC OFF via the NVCP there are horizontal lines across the screen, hard to see but still visible... it's hard to explain.

So far this is what I've tried to fix it:

Reinstalled Nvidia drivers with DDU

Full Windows reinstall (it needed to be done anyway!)

Changed DisplayPort Cable that came with the monitor to a "KabelDirekt – 8K DisplayPort cable version 1.4 (VESA certified, supports 8K 60 Hz, 4K 120 Hz, HBR3, DSC, HDR10, DP8K) – 2m"

Has anyone ever had this issue or does anyone have any advice on how to fix it please?

Build below if needed:

Intel 9900K @ 5.00ghz
EVGA 2080Ti FTW3 Ultra
Gigabyte Aorus Z390 Master
Corsair Vengeance RGB PRO 32 GB (4 x 8 GB) DDR4 3200 MHz
EVGA SuperNOVA 1000 G3, 80 Plus Gold 1000W
Custom EK loop

[Chief Blur Buster]

First issue, with G-SYNC ON (fullscreen or fullscreen / windowed) there is obvious "brightness flickering" on the desktop and within games which is incredibly annoying.

Brightness flickering is often caused by frame rate fluctuations since the different refresh rates sometimes have more LCD decay than others. Early VRR monitors had more issues with VRR flicker than newer VRR monitors. If you only use Full Screen, then windowed apps shouldn't be flickering (although maximized windows sometimes switch to the full screen G-SYNC mode)

Second issue, with G-SYNC OFF via the NVCP there are horizontal lines across the screen, hard to see but still visible... it's hard to explain.

That's an artifact from LCD inversion and can't be fixed by software. Barring firmware upgrades or inversion algorithm switches, try testing a lower refresh rate such as 120Hz.

Changed DisplayPort Cable that came with the monitor to a "KabelDirekt – 8K DisplayPort cable version 1.4 (VESA certified, supports 8K 60 Hz, 4K 120 Hz, HBR3, DSC, HDR10, DP8K) – 2m"

It won't help. I know these artifacts and it's not cable-related.

Have you considered a DisplayPort-to-DVI adaptor? Kinda expensive.
Or upgrading your monitor?

[KeyS]

Wow, I wasn't expecting such a quick reply and great explanations. Thank you!

In regards to switching to 120hz you're completely right, switched it down from 144hz and there are no lines / artifacts anymore.

I just had a look at the adaptor and a quick google showed one for £110 with 144hz capability, if they're that expensive I'd prefer to go down the new monitor route!

The XL2420G is getting quite old now but it's just been amazing running it with DVI for this long, it's annoying that they seem to be dying out as I'd have no use for a 240hz (only CS:GO manages those framerates) or anything higher than 1080p / bigger than 24.5".

Would one of the newer monitors say the "BenQ ZOWIE XL2540" eliminate the brightness flickering when using G-SYNC or is this a known issue across all monitors?

[KeyS]

I'm not sure if my last post submitted or not, either way thank you for your quick and detailed response again!

Since your advice I've been looking at new monitors and the BenQ ZOWIE XL2546 looks to be the best one however, it doesn't have Freesync or G-SYNC so I'm completely stuck on whether to stick without them or purchase the older XL2540 version.

I've never used Freesync or G-SYNC in the past and I mainly play FPS games very competitively like CS:GO, Rust and Escape from Tarkov but do notice screen tearing... is slight input lag worth having no tears that's the question. I'm a "1% / 1ms all add up" kind of person and it's frustrating having to choose this!

[Chief Blur Buster]

I'm not sure if my last post submitted or not, either way thank you for your quick and detailed response again!

Since your advice I've been looking at new monitors and the BenQ ZOWIE XL2546 looks to be the best one however, it doesn't have Freesync or G-SYNC so I'm completely stuck on whether to stick without them or purchase the older XL2540 version.

Or get the XL2546S. You get DyAc mode and FreeSync mode!
It's newly announced.

Mind you, I'm partial to 1ms IPS for my own person use but I certainly understand the performance of a 240Hz TN, and the BenQ ZOWIEs have tended to had top performance for that category, and so many pros use these monitors.

[KeyS]

Ok, wow... that changes things!

Is there any release date yet that you know of?

I did try the LG 27GL850-B and whilst the picture was amazing as granted with an IPS over a TN unfortunately I got unlucky with the glow lottery, one whole side was completely blinding.

However, when Cyberpunk is released I'll definitely be looking at purchasing a 1440p IPS panel again... it would be cruel to run such a game on a TN panel!

A final question about the "LCD inversion" you mentioned before and also the G-SYNC / Freesync flickering. Would a newer model monitor likely get rid of those issues?