9070 XT - 2x HDMI high refresh displays (144 and 120 Hz) not working

[King Mustard]

ASRock B650M Pro RS
AMD Ryzen 7 7800X3D
32 GB DDR5-6000
Corsair RM850x (2018) 850W PSU (manual)

I have just bought an RX 9070 XT, which will replace my RTX 3080.

I used the same PSU cable that I used with the RTX 3080 (page 6 of the manual, labelled 'PCIe 8 pin (6+2) cable').

I used Safe Mode and DDU to remove the NVIDIA drivers, and also used Safe Mode to install the latest Adrenalin v25.3.1 drivers.

I have a primary LG C4 (HDMI only) (144 Hz) and a secondary LG C2 (HDMI only) (120 Hz).

The RTX 3080 only had 1x HDMI port, so I used an active DP-HDMI adapter with the LC C2 and it all worked fine (144 Hz on the LG C4 and 120 Hz on the LG C2).

My new RX 9070 XT has 2x HDMI ports, so I was hoping to skip needing the DP-HDMI adapter.

When I connect the LG C4 on its own, it detects 144 Hz in Windows and I can play games with no problems - they run as exactly as they should (i.e. far quicker than the RTX 3080 did).

As soon as I connect the LC C2 (via HDMI), AMD's drivers say there are driver hangs (or something to that effect) and within a few seconds, the system locks up.

If I try to connect the LC C2 via DP (via that adapter), Windows detects it and I can use it a second display - but Windows is now detecting it only as having a max of 60 Hz (instead of 120 Hz that the display is capable of). When I try to force 120 Hz, I just get a black screen on the LG C2.

I am starting to already regret leaving NVIDIA.

Can anyone please assist?

 

[DaemonForce]

used Safe Mode to install the latest Adrenalin v25.3.1 drivers.

Is this part necessary?

I have a primary LG C4 (HDMI only) (144 Hz) and a secondary LG C2 (HDMI only) (120 Hz).

Do you have VRR enabled?

As soon as I connect the LC C2 (via HDMI), AMD's drivers say there are driver hangs (or something to that effect) and within a few seconds, the system locks up.

So the C4 is your main and C2 is secondary? What behaviors do you get if you just run the C2?

 

[mama]

Being an LG owner myself and learning that they are quirky, try different HDMI ports on your respective monitors. For some reason, my AMD GPU only works well with one of the four ports. After switching monitors, I determined it was the LG that was the issue.

 

[King Mustard]

Is this part necessary?

Do you have VRR enabled?

So the C4 is your main and C2 is secondary? What behaviors do you get if you just run the C2?

No but the drivers are designed to install perfectly in Safe Mode.

VRR is enabled on both TVs. The TVs are set up perfectly, as they worked perfectly with the RTX 3080.

If I run either display on their own, I get their full refresh rate (which is further evidence to me that there are no issues with the TVs).

Being an LG owner myself and learning that they are quirky, try different HDMI ports on your respective monitors. For some reason, my AMD GPU only works well with one of the four ports. After switching monitors, I determined it was the LG that was the issue.

Interesting. I will try this now, thank you. I will report back.

No but the drivers are designed to install perfectly in Safe Mode.

VRR is enabled on both TVs. The TVs are set up perfectly, as they worked perfectly with the RTX 3080.

If I run either display on their own, I get their full refresh rate (which is further evidence to me that there are no issues with the TVs).

Interesting. I will try this now, thank you. I will report back.

Unfortunately no change.

 

[_roman_]

If I run either display on their own, I get their full refresh rate (which is further evidence to me that there are no issues with the TVs).

Are you using the same cable and just switch on the monitor side?

Such refresh rates - especially with two meter length - need special quality display cables. I assume the ports on the graphic card and monitor side are to the spec without damage.

I am starting to already regret leaving NVIDIA.

whataboutism: of coures nvidia does not have many software and hardware issues with the 5000 graphic cards, right?
Maybe looking at intel ?


--

I'm not sure if these are the products in question.

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[King Mustard]

Are you using the same cable and just switch on the monitor side?

Such refresh rates - especially with two meter length - need special quality display cables. I assume the ports on the graphic card and monitor side are to the spec without damage.

Exact same cables I used with the RTX 3080 and they worked perfectly on that, so I know the cables are capable.

 

[3x0]

If I run either display on their own, I get their full refresh rate (which is further evidence to me that there are no issues with the TVs).

When you tested this, did you use the same cable to test both TVs?

 

[King Mustard]

When you tested this, did you use the same cable to test both TVs?

It worked perfectly with these cables in this order on my RTX 3080, so it should work equally as well with a straight GPU swap.

 

[3x0]

It's been shown previously that AMD cards don't play well with cables that are even slightly out of spec, especially on bigger lengths. So at least experiment to figure out if using one cable for both TVs individually works, and maybe the other cable is showing problems.

 

[King Mustard]

It's been shown previously that AMD cards don't play well with cables that are even slightly out of spec, especially on bigger lengths

That's a fault of AMD cards, then. They worked perfectly with my RTX 3080.

It is a shame, I will likely return the card and get a Nvidia 50 Series. It's not like there is a trusted source of certified cables. Not in the UK, anyway; and I am not going to import a HDMI cable.

 

[3x0]

It's not like there is a trusted source of certified cables.

Club3D makes pretty good cables. Anyways, good luck

 

[mama]

It worked perfectly with these cables in this order on my RTX 3080, so it should work equally as well with a straight GPU swap.

Did you try different HDMI ports on the LG?

 

[King Mustard]

Did you try different HDMI ports on the LG?

I have done.

I have also factory reset it.

 

[Frick]

Might be a driver issue. Send in a bug report so they'll know about it.

https://www.amd.com/en/resources/support-articles/faqs/AMDBRT.html

About cables: Cables working on one system might not work in others. It sucks, but there is where things are.

 

[_roman_]

Cables are an easy fix. Cable length and let's phrase it cable quality is still an issue up to date.

dp 2.1a is very new. My Powercolor 7800xt hellhound has only dp 2.1, not dp 2.1a
I'm well aware of that the poster connects his screen with HDMI. Still it shows that bandwidth and cable quality still matters even in 2025. especially with two 4k screens with over 120hz refresh rate each.

Just for information:

https://sg.msi.com/blog/what-are-dp21-and-dp21a-the-difference-you-ought-to-know

However, DP2.1 has a shortcoming “The Length of Cable”. To achieve faster transmission speeds, the trade-off is sacrificing cable length. The cable only has 1 meter. If the cable is longer, it may have some issues like latency or loss of performance. So this drawback limits the usability of DP2.1. A cable length of only 1 meter is quite challenging for practical use, especially since PC users often place their monitors away from their computers. ......

DisplayPort 2.1a (DP2.1a)​

DP2.1a is the newest standard which VESA launched at CES 2024. DP2.1a improves the bandwidth and extends the cable length. DP2.1a fixes the shortcoming of DP2.1. For DP54, it supports 2-meter-long cable without losing the performance. Generally, 2 meters is very enough for use.

If you are unhappy return the graphic card. Its your decission. Could be a driver issue which may be fixed quite soon or could be a cable "quality" issue. That was my motivation why i asked.

 

[Harakiry]

Did you find solution ? Cause I have the exact same issue. C4+C2 and I can't even manage make them both 4k. If I plug just one of either they can do max specs 144/120hz 4k hdr no problem but when i plug both one stays 4k/120 second goes FHD30hz

 

[_roman_]

Did you find solution ? Cause I have the exact same issue. C4+C2 and I can't even manage make them both 4k. If I plug just one of either they can do max specs 144/120hz 4k hdr no problem but when i plug both one stays 4k/120 second goes FHD30hz

Please provide more data. It s like someone says my car does not drive. My car is beige.

 

[tommesfps]

Hi,
please try hdmi to hdmi on the C4 and set it to 120Hz/60Hz instead of 144Hz, then try to connect the C2 with hdmi to hdmi , what does it show, only 4K@60?
which of the color options do you get by setting up 4K@144Hz on the C4, RGB full/limited or YCbCr 4:4:4 / 4:2:2 / 4:2:0 ?

edit: *I would take a guess, even though it worked with the RTX 3080 somehow, but maybe because the NVidia driver set different color space to meet the bandwidth of the cables by auto negotiation*

 

[GhostRyder]

ASRock B650M Pro RS
AMD Ryzen 7 7800X3D
32 GB DDR5-6000
Corsair RM850x (2018) 850W PSU (manual)

I have just bought an RX 9070 XT, which will replace my RTX 3080.

I used the same PSU cable that I used with the RTX 3080 (page 6 of the manual, labelled 'PCIe 8 pin (6+2) cable').

I used Safe Mode and DDU to remove the NVIDIA drivers, and also used Safe Mode to install the latest Adrenalin v25.3.1 drivers.

I have a primary LG C4 (HDMI only) (144 Hz) and a secondary LG C2 (HDMI only) (120 Hz).

The RTX 3080 only had 1x HDMI port, so I used an active DP-HDMI adapter with the LC C2 and it all worked fine (144 Hz on the LG C4 and 120 Hz on the LG C2).

My new RX 9070 XT has 2x HDMI ports, so I was hoping to skip needing the DP-HDMI adapter.

When I connect the LG C4 on its own, it detects 144 Hz in Windows and I can play games with no problems - they run as exactly as they should (i.e. far quicker than the RTX 3080 did).

As soon as I connect the LC C2 (via HDMI), AMD's drivers say there are driver hangs (or something to that effect) and within a few seconds, the system locks up.

If I try to connect the LC C2 via DP (via that adapter), Windows detects it and I can use it a second display - but Windows is now detecting it only as having a max of 60 Hz (instead of 120 Hz that the display is capable of). When I try to force 120 Hz, I just get a black screen on the LG C2.

I am starting to already regret leaving NVIDIA.

Can anyone please assist?

Which card do you have specifically?

 

[rv8000]

I don’t have the exact setup you do but I have a triple monitor setup and use a 48” c2 for occasional games/lounging, might run into a similar issue and I haven’t checked the signal on the c2 since swapping; 1440p/240, 1440p/165, 4k/120 (dp,dp,hdmi).

I will investigate when home. FWIW, I use a 30’ optical HDMI cable from Rupiro, so that alone may change my out come.

 

[Sir Beregond]

Easiest thing to start with is probably ensuring you are using certified HDMI 2.1 cables no longer than probably 2 meters (about 6.6 feet). I'd also then make sure both screens are set to 120hz and not 144hz for the C4 and see how that goes. I wonder if when using both HDMI ports at the same time if the refresh rate limit is 120.

Odd though that even using the old setup with the active HDMI to DP adapter it's even more problematic.

I have three C-series OLED's in the house currently, but never tried to use two at the same time. Started with 48" C1, but was slightly too big for my desk so I use it as a TV now and moved to a 42" C4 that I have had no issues with. My wife got a refurb 42" C3 last year but it kept flashing snowy screens briefly after ruling out cables, drivers, GPUs, etc, so it went back and got a new C4. That C4 died a month later, and also got replaced under warranty (Micro Center rocks).

EDIT: I wonder also if DDU really did take care of everything when switching drivers. To me this feels driver related if the cables and such have been ruled out.

 

[King Mustard]

I don’t have the exact setup you do but I have a triple monitor setup and use a 48” c2 for occasional games/lounging, might run into a similar issue and I haven’t checked the signal on the c2 since swapping; 1440p/240, 1440p/165, 4k/120 (dp,dp,hdmi).

I will investigate when home. FWIW, I use a 30’ optical HDMI cable from Rupiro, so that alone may change my out come.

I created a thread about this on the Overclockers UK forum and also sent an AMD vendor representative on there my crash logs.

So far, I have not heard anything but hopefully, he will address it on the forum or AMD will address it within the next few driver updates.

Maybe you could jump into the thread and explain how similar your issue is?

 

[GhostRyder]

I created a thread about this on the Overclockers UK forum and also sent an AMD vendor representative on there my crash logs.

So far, I have not heard anything but hopefully, he will address it on the forum or AMD will address it within the next few driver updates.

Maybe you could jump into the thread and explain how similar your issue is?

What kind of adaptor are you using for DP to HDMI?

 

[King Mustard]

What kind of adaptor are you using for DP to HDMI?

I bought this model of RX 9070 XT specifically because it has 2x HDMI ports, so I no longer needed an active adapter.

However, when I use both (certified) HDMI cables straight into the GPU, I get the driver timeouts and the system locks.

At least I can currently get both displays working, via using the adapter as I did on the RTX 3080, though it means locking the C2 (secondary) display to 60 Hz. Which is not an adapter limitation, it worked perfectly with the RTX 3080.

This is an AMD issue, nothing on my end.

Hopefully, they can fix it via a driver update.

 

[GhostRyder]

I bought this model of RX 9070 XT specifically because it has 2x HDMI ports, so I no longer needed an active adapter.

However, when I use both (certified) HDMI cables straight into the GPU, I get the driver timeouts and the system locks.

At least I can currently get both displays working, via using the adapter as I did on the RTX 3080, though it means locking the C2 (secondary) display to 60 Hz. Which is not an adapter limitation, it worked perfectly with the RTX 3080.

This is an AMD issue, nothing on my end.

Hopefully, they can fix it via a driver update.

I am not saying its not, I was curious if there was a work around (At least as a temp solution) using a different DP adaptor since your current one was limiting the TV. My friends RX 6900 uses DP monitors with two different high refresh setups and its not having that issue that I am aware of (His main is a 1440p 144hz monitor and the other is some 1440p 120hz monitor).