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

King Mustard · 2025-03-09T22:03:19+0000

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 · 2025-03-09T22:09:57+0000

King Mustard said:
used Safe Mode to install the latest Adrenalin v25.3.1 drivers.

Is this part necessary?

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

Do you have VRR enabled?

King Mustard said:
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 · 2025-03-09T22:12:56+0000

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 · 2025-03-09T22:13:51+0000

DaemonForce said:
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).

mama said:
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.

King Mustard said:
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_ · 2025-03-10T00:21:20+0000

King Mustard said:
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.

King Mustard said:
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 · 2025-03-10T00:35:55+0000

_roman_ said:
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 · 2025-03-10T00:46:12+0000

King Mustard said:
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 · 2025-03-10T00:48:04+0000

3x0 said:
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 · 2025-03-10T00:49:33+0000

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 · 2025-03-10T00:52:21+0000

3x0 said:
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 · 2025-03-10T00:59:27+0000

King Mustard said:
It's not like there is a trusted source of certified cables.

Club3D makes pretty good cables. Anyways, good luck

mama · 2025-03-10T04:53:03+0000

King Mustard said:
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 · 2025-03-10T07:46:01+0000

mama said:
Did you try different HDMI ports on the LG?

I have done.

I have also factory reset it.

Processor	AMD Ryzen 7 7800X3D
Motherboard	ASRock B650M Pro RS
Cooling	Arctic Liquid Freezer II 240 A-RGB
Memory	32 GB DDR5-6000
Video Card(s)	NVIDIA GeForce RTX 3080
Storage	Samsung 990 Pro
Display(s)	2x 42" 4K OLED (LG C4, LG C2)
Case	Cooler Master MasterBox NR400
Audio Device(s)	Logitech Z906
Power Supply	Corsair RM850x (2018)
Mouse	Logitech G305
Keyboard	Tecware Phantom RGB (105-key)
Software	Windows 11

System Name	DevKit
Processor	AMD Ryzen 5 3600 ↗4.0GHz
Motherboard	Asus TUF Gaming X570-Plus WiFi
Cooling	Koolance CPU-300-H06, Koolance GPU-180-L06, SC800 Pump
Memory	4x16GB Ballistix 3200MT/s ↗3800
Video Card(s)	PowerColor RX 580 Red Devil 8GB ↗1380MHz ↘1105mV, PowerColor RX 7900 XT Hellhound 20GB
Storage	240GB Corsair MP510, 120GB KingDian S280
Display(s)	Nixeus VUE-24 (1080p144)
Case	Koolance PC2-601BLW + Koolance EHX1020CUV Radiator Kit
Audio Device(s)	Oculus CV-1
Power Supply	Antec Earthwatts EA-750 Semi-Modular
Mouse	Easterntimes Tech X-08, Zelotes C-12
Keyboard	Logitech 106-key, Romoral 15-Key Macro, Royal Kludge RK84
VR HMD	Oculus CV-1
Software	Windows 10 Pro Workstation, VMware Workstation 16 Pro, MS SQL Server 2016, Fan Control v120, Blender
Benchmark Scores	Cinebench R15: 1590cb Cinebench R20: 3530cb (7.83x451cb) CPU-Z 17.01.64: 481.2/3896.8 VRMark: 8009

System Name	1. Glasshouse 2. Odin OneEye
Processor	1. Ryzen 9 5900X (manual PBO) 2. Ryzen 9 7900X
Motherboard	1. MSI x570 Tomahawk wifi 2. Gigabyte Aorus Extreme 670E
Cooling	1. Noctua NH D15 Chromax Black 2. Custom Loop 3x360mm (60mm) rads & T30 fans/Aquacomputer NEXT w/b
Memory	1. G Skill Neo 16GBx4 (3600MHz 16/16/16/36) 2. Kingston Fury 16GBx2 DDR5 CL36
Video Card(s)	1. Asus Strix Vega 64 2. Powercolor Liquid Devil 7900XTX
Storage	1. Corsair Force MP600 (1TB) & Sabrent Rocket 4 (2TB) 2. Kingston 3000 (1TB) and Hynix p41 (2TB)
Display(s)	1. Samsung U28E590 10bit 4K@60Hz 2. LG C2 42 inch 10bit 4K@120Hz
Case	1. Corsair Crystal 570X White 2. Cooler Master HAF 700 EVO
Audio Device(s)	1. Creative Speakers 2. Built in LG monitor speakers
Power Supply	1. Corsair RM850x 2. Superflower Titanium 1600W
Mouse	1. Microsoft IntelliMouse Pro (grey) 2. Microsoft IntelliMouse Pro (black)
Keyboard	Leopold High End Mechanical
Software	Windows 11

Processor	AMD Ryzen 7 7800X3D
Motherboard	ASRock B650M Pro RS
Cooling	Arctic Liquid Freezer II 240 A-RGB
Memory	32 GB DDR5-6000
Video Card(s)	NVIDIA GeForce RTX 3080
Storage	Samsung 990 Pro
Display(s)	2x 42" 4K OLED (LG C4, LG C2)
Case	Cooler Master MasterBox NR400
Audio Device(s)	Logitech Z906
Power Supply	Corsair RM850x (2018)
Mouse	Logitech G305
Keyboard	Tecware Phantom RGB (105-key)
Software	Windows 11

Processor	AMD Ryzen 7 7800X3D
Motherboard	ASRock B650M Pro RS
Cooling	Arctic Liquid Freezer II 240 A-RGB
Memory	32 GB DDR5-6000
Video Card(s)	NVIDIA GeForce RTX 3080
Storage	Samsung 990 Pro
Display(s)	2x 42" 4K OLED (LG C4, LG C2)
Case	Cooler Master MasterBox NR400
Audio Device(s)	Logitech Z906
Power Supply	Corsair RM850x (2018)
Mouse	Logitech G305
Keyboard	Tecware Phantom RGB (105-key)
Software	Windows 11

Processor	AMD Ryzen 7 5800X3D
Motherboard	MSI MPG B550I Gaming Edge Wi-Fi ITX
Cooling	Scythe Fuma 2 rev. B Noctua NF-A12x25 Edition
Memory	2x16GiB G.Skill TridentZ DDR4 3200Mb/s CL14 F4-3200C14D-32GTZKW
Video Card(s)	PowerColor Radeon RX7800 XT Hellhound 16GiB Noctua NF-A12x25 Edition
Storage	Western Digital Black SN850 WDS100T1X0E-00AFY0 1TiB, Western Digital Blue 3D WDS200T2B0A 2TiB
Display(s)	Dell G2724D 27" IPS 1440P 165Hz, ASUS VG259QM 25” IPS 1080P 240Hz
Case	Cooler Master NR200P ITX
Audio Device(s)	Altec Lansing 220, HyperX Cloud II
Power Supply	Corsair SF750 Platinum 750W SFX
Mouse	Endgame Gear OP1 8K
Keyboard	HyperX Alloy Origins Aqua