Question Fringing when using Windows at 120 Hz

[Bobsy]

Hello! Last year, I purchased a Dell S2721DGF monitor. It supports up to 165 Hz refresh rate. It is connected to a GTX 1060 GPU.
Recently, a friend asked me if I had changed the refresh rate in Windows 10 from 60 Hz to 120 Hz. I had not. When I tried, everything was OK except that visual artefacts made the text harder to read. I believe what I saw is called fringing.
Is this normal? Does anyone know what's going on? Thanks!

 

[mnewsham]

I'd suggest using DP 1.4 if you're not already instead of HDMI, running at 144hz or 165hz and in the Nvidia settings make sure you're using 4:4:4/RGB not 4:2:0 or 4:2:2

The Rtings review for this monitor says it has decent text clarity at all refresh rates, though they do still recommend using W10 "ClearType" to make text a bit more legible.

 

[Bobsy]

Thank you for your reply, @mnewsham, you are giving me hope!

I'm already using DisplayPort, so that's good.

I'm only given two refresh rate options: 60 Hz and 120 Hz. I don't know why I don't have 144 Hz.

When I select 120 Hz (and get fringing), the NVIDIA color setting change to these:
Desktop color depth: Highest (32-bit) [this one did not change]
Output color depth: 8 bpc [drops from 10 bpc, and is the only option available]
Output color format: YCbCr422 [this is the only option available]
Output dynamic range: Limited [this is the only option available]

Any idea what's wrong? All the latest drivers are installed.

 

[Bobsy]

I just tried setting color format to YCbCr422 while keeping the refresh rate at 60 Hz and fringing appears. This is the problem is coming from. I don't know how to resolve it... I'm starting to wonder if I'm getting FPS higher than 60 Hz in games...

 

[mnewsham]

I'd suggest changing your displayport cable, it sounds like it's only operating at HBR speeds (displayport 1.0), but since both your GPU, and your monitor support DP1.4, my assumption is you have a poor quality cable, or it's potentially damaged.

 

[Tup3x]

Pascal GPUs didn't have proper support for DP1.4 out of the box (at least if they were old enough). They required firmware update: https://www.nvidia.com/en-us/drivers/nv-uefi-update-x64/

 

[mnewsham]

Pascal GPUs didn't have proper support for DP1.4 out of the box (at least if they were old enough). They required firmware update: https://www.nvidia.com/en-us/drivers/nv-uefi-update-x64/

Even so, they should support still DP1.2 (HBR2 @ ~17gbps) which would still be more than enough for 1440p 165hz at 4:4:4 which is only 16.3gbps.

In any case though, my guess is on a damaged/poor quality cable as that's how the DP spec treats lower quality cables, it just runs them at a lower speed that is stable.

If the quality of the DisplayPort cable is insufficient to reliably handle HBR2 speeds for example, the DisplayPort devices will detect this and switch down to a lower mode to maintain a stable connection.

 

[Muadib]

Thank you for your reply, @mnewsham, you are giving me hope!

I'm already using DisplayPort, so that's good.

I'm only given two refresh rate options: 60 Hz and 120 Hz. I don't know why I don't have 144 Hz.

When I select 120 Hz (and get fringing), the NVIDIA color setting change to these:
Desktop color depth: Highest (32-bit) [this one did not change]
Output color depth: 8 bpc [drops from 10 bpc, and is the only option available]
Output color format: YCbCr422 [this is the only option available]
Output dynamic range: Limited [this is the only option available]

Any idea what's wrong? All the latest drivers are installed.

When you click to change your refresh rate, click on 120 Hz, and then hit the down arrow to see 144Hz. I had the same problem back when I first got my 144Hz monitor.

 

[mnewsham]

When you click to change your refresh rate, click on 120 Hz, and then hit the down arrow to see 144Hz. I had the same problem back when I first got my 144Hz monitor.

Can't say I've ever experienced that personally, but I guess it could just depend on the panel in question.

 

[Bobsy]

Thank you so much to everyone. @mnewsham was right! I updated the firmware (upgrade was needed), but that alone wasn’t enough. (Still a good thing to do, so thank you @Tup3x) Then I replaced the DP cable and everything worked! You should have seen the smile on my face. I’ve been using this monitor for five months and had never experienced FPS higher than 60 Hz. I used Windows for a few minutes and the difference is obvious.
Thank you to this amazing community. I am very grateful for the help I received.