Dell s3422dwg can't display 3440x1440 @ 144hz w/ HDR (windows 11)

[astro_man26]

Hey guys/gals,

 

Just bought a Dell s3422dwg ultrawide and I can't seem to figure out how to get the full resolution (3440x1440) at the full refresh rate (144hz) with HDR enabled on DP1.4 in Windows 11

 

I have two other monitors plugged in

- Dell's S2721DS (1440p @ 75hz) plugged in with DP cable

- Dell S2340L (1080p @ 60hz) plugged in with HDMI cable

 

I am using the DP cable which was provided with the monitor and it is plugged in my RX480 (supports DisplayPort™ 1.3 HBR3, and DisplayPort 1.4 HDR support according to AMD)

 

If I enable HDR it either flickers and turns off or it shows a weird cropped and pixelated view of the desktop.

What could be the cause? Lack of bandwidth? the RX480 not fully supporting DP 1.4? I have the feeling from the reading I've been doing on the topic that early DP 1.4 cards did not have DSC (Display Stream Compression) support and it might be why I can't all the goodies turned on.

 

I would upgrade my GPU... but... you know... the market...

 

Thanks!

[tkitch]

Try the HDMI Port and see how it goes?

It's HDMI 2.0B on your card, so that should get you most of the way to 144Hz?   

[Stahlmann]

10 minutes ago, astro_man26 said:

I have the feeling from the reading I've been doing on the topic that early DP 1.4 cards did not have DSC (Display Stream Compression) support and it might be why I can't all the goodies turned on.

DSC only started to get implemented on Nvidia's 10 series and AMDs 5000 series afaik.

 

It's not a bandwidth limitation either way:

[astro_man26]

1 hour ago, tkitch said:

Try the HDMI Port and see how it goes?

It's HDMI 2.0B on your card, so that should get you most of the way to 144Hz?   

HDMI is limited to 100Hz on this monitor, as per Dell's spec sheets and user manual

 

[astro_man26]

1 hour ago, Stahlmann said:

DSC only started to get implemented on Nvidia's 10 series and AMDs 5000 series afaik.

 

It's not a bandwidth limitation either way:

 

Could the combined bandwidth required for the throughput to 3 monitors have an impact on an individual output or do graphics cards have plenty of bandwidth for outputting to multiple monitors, all the while maxing at least one port?

 

EDIT:  Easy check... turned off both my secondary monitors and I'm still having the issue. It is not a bandwith issue due to multiple monitors.

[Glenwing]

Possible inadequate cable unable to handle HBR3 speed. Are you using the one that came with the monitor?

[astro_man26]

2 hours ago, astro_man26 said:

 

Could the combined bandwidth required for the throughput to 3 monitors have an impact on an individual output or do graphics cards have plenty of bandwidth for outputting to multiple monitors, all the while maxing at least one port?

 

EDIT:  Easy check... turned off both my secondary monitors and I'm still having the issue. It is not a bandwith issue due to multiple monitors.

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