2nd monitor won't display @ 144hz

[vyrotek]

Hello. I just switched over to Aurora-dx Beta (coming from Bazzite-dx).

I have 2 monitors with 144hz refresh rates. But for some odd reason, I can only get my 2nd monitor to display anything when I set it to 120hz. At 144hz it's still detected, but no signal. The 1st monitor always works fine @ 144hz. Using a 3rd portable monitor @ 60hz works too.

I wasn't sure where to start looking into this. They both worked with Bazzite @ 144hz.

Is this a Aurora issue? beta? drivers? Thanks for your help.

[repires]

Ai generated: ask.projectbluefin.io

https://app.dosu.dev/e3630b91-3a35-46b9-a8d3-b0c1b3ef6331/ask?dosuAnswered=with-dosu&thread=be962f18-6990-400f-b177-2d31561e414a

You can try to start debugging there.

This is a tricky one to pin down without more hardware details, but here are some things to check and try:

Gather diagnostics first — this will help narrow down the cause:

# Check GPU and driver info
lspci | grep -i vga
lsmod | grep -E 'amdgpu|nvidia|i915'

# Check current kernel
uname -r

# Check what Aurora image you're on
bootc status

Likely causes and things to try:

1. KDE vs GNOME compositor differences — Aurora uses KDE (Plasma/KWin), while Bazzite also uses KDE but may ship different compositor settings or kernel parameters. Since both monitors worked on Bazzite at 144Hz, the issue is likely in how KWin is negotiating the display mode on Aurora Beta. Try toggling Settings → Display and Monitor → Adaptive Sync / VRR off (or on) and see if that changes behavior.

2. Cable/port bandwidth — If both monitors are on the same GPU output (e.g., via a hub or daisy-chain), bandwidth limits could prevent dual 144Hz. But since this worked on Bazzite, this is less likely unless Aurora Beta ships a different kernel version that changed link training behavior.

3. Try the amdgpu.dcdebugmask=0x410 kernel parameter — this has resolved various AMD display issues including refresh rate problems on Bluefin/Aurora :

   sudo rpm-ostree kargs --append-if-missing amdgpu.dcdebugmask=0x410
   sudo systemctl reboot

4. Check if it's a beta/kernel regression — Since you're on the Beta channel, you may be running a newer kernel than Bazzite was. Try booting an older deployment from GRUB to see if the issue is kernel-specific. You can also check available deployments with bootc status.

5. Manually set the mode via KScreen — Sometimes the auto-negotiated mode differs from what the monitor reports. Open kscreen-doctor --outputs to see what modes are available for each output, and try forcing 144Hz explicitly.

What would help narrow this down further:

• What GPU do you have (AMD, NVIDIA, Intel)?
• Are you using DisplayPort, HDMI, or a mix?
• What kernel version are you on (uname -r)?

The fact that it works at 120Hz but not 144Hz on only the second monitor strongly suggests a link training or bandwidth negotiation issue at the kernel/driver level rather than an Aurora-specific configuration problem.

[vyrotek]

This looks like a possible regression.

I booted back to 43 and they both worked set at 144hz.

Operating System: Aurora 43
KDE Plasma Version: 6.6.3
KDE Frameworks Version: 6.24.0
Qt Version: 6.10.2
Kernel Version: 6.18.13-200.fc43.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 3600 6-Core Processor
Memory: 48 GiB of RAM (47.0 GiB usable)
Graphics Processor: NVIDIA GeForce GTX 1660 SUPER
Manufacturer: Micro-Star International Co., Ltd
Product Name: MS-7C02
System Version: 1.0

Booting to 44 Beta, the 2nd monitor was recognized, set to 144hz, can move my mouse over, but no signal.

Operating System: Aurora 44
KDE Plasma Version: 6.6.3
KDE Frameworks Version: 6.24.0
Qt Version: 6.10.2
Kernel Version: 6.19.10-300.fc44.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 3600 6-Core Processor
Memory: 48 GiB of RAM (47.0 GiB usable)
Graphics Processor: NVIDIA GeForce GTX 1660 SUPER
Manufacturer: Micro-Star International Co., Ltd
Product Name: MS-7C02
System Version: 1.0

lspci | grep -i vga

26:00.0 VGA compatible controller: NVIDIA Corporation TU116 [GeForce GTX 1660 SUPER] (rev a1)

lsmod | grep -E 'amdgpu|nvidia|i915'

i2c_nvidia_gpu 16384 0

kscreen-doctor --output

Screen 1 (Working)

Output: 1 DP-1 52b53a6c-b454-44e9-944d-7cb6f2ccaad1
enabled
connected
priority 1
DisplayPort
replication source:0
Modes: 1:2560x1440@144.00*! 2:2560x1440@120.00 3:2560x1440@99.90 4:2560x1440@59.95 5:1920x1080@74.98 6:1920x1080@60.00 7:1920x1080@60.00 8:1920x1080@59.94 9:1920x1080@50.00 10:1680x1050@59.95 11:1600x900@60.00 12:1280x1024@75.03 13:1280x1024@60.02 14:1280x800@59.81 15:1152x864@59.97 16:1280x720@60.00 17:1280x720@59.94 18:1280x720@50.00 19:1024x768@75.03 20:1024x768@60.00 21:800x600@75.00 22:800x600@60.32 23:720x480@60.00 24:720x480@59.94 25:640x480@75.00 26:640x480@60.00 27:640x480@59.94 28:1600x1200@59.87 29:1600x1200@143.89 30:1280x1024@143.79 31:1024x768@143.87 32:1920x1200@59.88 33:1920x1200@143.89 34:1280x800@143.84 35:1920x1080@143.88 36:1600x900@143.93 37:1368x768@59.88 38:1368x768@143.77 39:1280x720@143.67
Custom modes: None
Geometry: 0,0 2560x1440
Scale: 1
Rotation: 1
Overscan: 0
Vrr: incapable
RgbRange: unknown
HDR: incapable
Wide Color Gamut: incapable
ICC profile: none
Color profile source: sRGB
Color power preference: prefer accuracy
Brightness control: unsupported
DDC/CI: allowed
Color resolution: unknown
Allow EDR: unsupported
Sharpness control: unsupported
Automatic brightness: unsupported

Screen 2 (Not Working)

Output: 2 DP-2 cbcc9384-2094-4240-b7e4-fbdff9ec7729
enabled
connected
priority 2
DisplayPort
replication source:0
Modes: 40:2560x1440@144.00*! 41:2560x1440@120.00 42:2560x1440@99.90 43:2560x1440@59.95 44:1920x1440@75.00 45:1920x1440@60.00 46:1856x1392@75.00 47:1856x1392@59.99 48:1792x1344@75.00 49:1792x1344@60.00 50:2048x1152@60.00 51:1920x1200@84.93 52:1920x1200@74.93 53:1920x1200@59.88 54:1920x1080@74.99 55:1920x1080@60.00 56:1920x1080@60.00 57:1920x1080@59.94 58:1920x1080@50.00 59:1600x1200@85.00 60:1600x1200@75.00 61:1600x1200@70.00 62:1600x1200@65.00 63:1600x1200@60.00 64:1680x1050@84.94 65:1680x1050@74.89 66:1680x1050@59.95 67:1680x945@60.02 68:1400x1050@84.96 69:1400x1050@74.87 70:1400x1050@59.98 71:1600x900@60.00 72:1280x1024@85.02 73:1280x1024@75.03 74:1280x1024@60.02 75:1440x900@84.84 76:1440x900@74.98 77:1440x900@59.89 78:1280x960@85.00 79:1280x960@60.00 80:1366x768@59.79 81:1360x768@60.01 82:1280x800@84.88 83:1280x800@74.93 84:1280x800@59.81 85:1152x864@75.00 86:1152x864@59.97 87:1280x768@84.84 88:1280x768@74.89 89:1280x768@59.87 90:1280x720@60.00 91:1280x720@59.94 92:1280x720@50.00 93:1024x768@85.00 94:1024x768@75.03 95:1024x768@70.07 96:1024x768@60.00 97:1024x576@59.97 98:800x600@85.06 99:800x600@75.00 100:800x600@72.19 101:800x600@60.32 102:800x600@56.25 103:848x480@60.00 104:720x480@60.00 105:720x480@59.94 106:640x480@85.01 107:640x480@75.00 108:640x480@72.81 109:640x480@60.00 110:640x480@59.94 111:720x400@85.04 112:640x400@85.08 113:640x350@85.08 114:1600x1200@143.89 115:1280x1024@143.79 116:1024x768@143.87 117:1920x1200@143.89 118:1280x800@143.84 119:1920x1080@143.88 120:1600x900@143.93 121:1368x768@59.88 122:1368x768@143.77 123:1280x720@143.67
Custom modes: None
Geometry: 2560,0 2560x1440
Scale: 1
Rotation: 1
Overscan: 0
Vrr: incapable
RgbRange: unknown
HDR: incapable
Wide Color Gamut: incapable
ICC profile: none
Color profile source: sRGB
Color power preference: prefer accuracy
Brightness control: unsupported
DDC/CI: allowed
Color resolution: unknown
Allow EDR: unsupported
Sharpness control: unsupported
Automatic brightness: unsupported

[repires]

Dosu feedback:
https://app.dosu.dev/e3630b91-3a35-46b9-a8d3-b0c1b3ef6331/ask?dosuAnswered=with-dosu&thread=be962f18-6990-400f-b177-2d31561e414a

Great diagnostic work — this is a clear kernel regression. The fact that both monitors work fine at 2560x1440@144Hz on kernel 6.18.13 but the second DP output goes no-signal on kernel 6.19.10 (with identical KDE Plasma / Qt / KDE Frameworks versions) isolates this squarely to a kernel or nvidia-open driver change.

I didn't find this specific issue reported in the Bluefin/Aurora trackers — most documented kernel 6.17–6.19 display regressions have been AMD-related. This looks like it may be a new/unreported NVIDIA regression, possibly in DRM/KMS link training for multi-head DisplayPort on Turing GPUs (TU116).

One notable thing from your lsmod output: only i2c_nvidia_gpu shows up in the grep — the main nvidia module isn't listed there. That could just be the grep filter, but worth double-checking that the full driver stack is loaded:

lsmod | grep nvidia

For now, your best options:

1. Stay on Aurora 43 / kernel 6.18 — since it works, pin that deployment so it doesn't get garbage-collected:

   sudo ostree admin pin 0

2. Grab kernel logs from the broken boot — this would help if you want to report it upstream:

   # Boot into 44 Beta, then:
   journalctl -b | grep -iE 'nvidia|drm|DP-2' > ~/nvidia-dp-regression.log

   Look for link training failures, DPCD errors, or DRM atomic commit failures on DP-2.

3. File a bug — since Aurora 44 is Beta / Fedora 44, this is worth reporting:

   • Fedora kernel bugzilla (kernel 6.19 regression, NVIDIA TU116 DP multi-monitor)
   • NVIDIA open-gpu-kernel-modules GitHub (if the regression is in the nvidia-open driver rather than the kernel DRM layer)

   Include the kernel version bisect (6.18.13 works, 6.19.10 broken), GPU model, and the kscreen-doctor output you already gathered.

4. Optional experiment — try forcing the second monitor to 120Hz on kernel 6.19 via kscreen-doctor to confirm the workaround still holds:

   kscreen-doctor output.2.mode.41

This is almost certainly an upstream kernel or nvidia-open driver issue rather than anything Aurora-specific, since the KDE/Plasma/Wayland stack is identical between both boots.