Framework Desktop + LG 6K: DSC inactive, stuck at 6K@30 (no 6K@60)

[kvz]

Summary

Framework Desktop (AMD Strix Halo iGPU) + LG UltraFine 6K over DisplayPort cannot run 6K@60. DSC is detected but never activates, so Hyprland only works at 6K@30 (or 4K@60). Tried latest Arch linux-git (6.18.0-1-git-12189-g67a454e6b1c6) – it crashes early (BUG in lib/string_helpers), so we fell back to stable. Docs say Omarchy targets 6K “retina 2x”, so this feels like a gap folks will hit on this hardware.

Hardware / Setup

• Machine: Framework Desktop (AMD Ryzen AI Max 300 Series / Strix Halo)
• GPU: iGPU (amdgpu)
• Display: LG UltraFine 6K (6144x3456) via DP
• DE: Hyprland (Omarchy defaults)
• Current working mode: 6K @ 30 Hz, scale 2.0 (fallback); 4K @ 60 Hz also works.
• Desired: 6K @ 60 Hz.

Current state (stable Arch kernel 6.17.9-arch1-1)

$ sudo ./bin/check-dsc.sh
Using debugfs: /sys/kernel/debug/dri/0000:c2:00.0 (DP-1)
== Link settings ==
Current:  4  0x14  0  Verified:  4  0x3e8  16 Reported:  4  0x546  16 Preferred:  0  0x0  0
== BPC ==
max_bpc: 8
output_bpc: Maximum: 10
== DSC ==
dp_dsc_fec_support: FEC_Sink_Support: yes
DSC_Sink_Support: yes
dsc_clock_en: 0
dsc_bits_per_pixel: 0
Summary: DSC supported=no, active=no on DP-1

Attempted newer DC via linux-git

• Installed linux-git (6.18.0-1-git-12189-g67a454e6b1c6) and set Limine to default.
• Boot hits a kernel BUG early and never reaches GUI.
• Kernel log excerpt (from journalctl -b -1 -k):

strnlen: detected buffer overflow: 17 byte read of buffer size 16
WARNING: lib/string_helpers.c:1035 …
…
kernel BUG at lib/string_helpers.c:1043!
Oops: invalid opcode: 0000 [#1] SMP NOPTI
Modules linked in: … amdgpu …
Tainted: G        W           6.18.0-1-git-12189-g67a454e6b1c6 …

Ask

1. Could the docs mention current AMD DSC limitations on Strix Halo / Framework Desktop and recommend the known-stable fallback (6K@30 or 4K@60) until DSC is active?
2. If you have a known-good kernel config/branch where DC enables DSC on this hardware, I’m happy to test.
3. If there’s a preferred upstream bug to follow (drm/amd), I can file it with these logs.

Why this matters

Omarchy advertises “retina-class 2x displays … 32" 6K” as defaults; Framework actively promoted Omarchy. Users on this exact combo will likely hit the same wall.

Thanks! Happy to provide more logs or try patches.

[kvz]

I should probably add that when I try the very same monitor and DisplayPort cable on a Beelink SER9, it just works:

$ hyprctl monitors
Monitor DP-1 (ID 0):
        6144x3456@60.02100 at 0x0
        description: LG Electronics LG ULTRAFINE 509NTWGMB721
...
        scale: 2.00
...

I just think it's odd because I would have expected the Framework Desktop to be a smooth upgrade, walking the golden path, adopting advertised hardware, but for some reason it's not 🤔

[dhh]

Interesting. I've been using the Framework Desktop with a 6K Apple XDR without problems. But that's through a DisplayPort+USB-A=>USB-C cable. Haven't tried any 6K monitor with a direct DisplayPort connection. Maybe @eclecticc can help point us at someone at Framework that could take it further.

[whargrove]

@kvz I have similar setup: LG UltraFine 6K and Framework Desktop.

I get 6K@60Hz using USB-4 and DisplayPort on 6.17.8-arch1-1. (Fresh install from latest Omarchy ISO.)

However, I loose video on the plymouth splash screen.

Limine - ✅ Video
Plymouth - ⛔ No Video
Hyprland - ✅ Video

I can enter my passphrase blind and system proceeds to start hyprland.

[kvz]

@whargrove thanks I missed this update but xmas holidays gave me some tinker time and I bumped upon the same!

Initially I had thought that the usb-c ports on the back of the framework desktop didn't support Thunderbolt 5 (they don't) and that that would be a requirement for 6k@60hz. But I was wrong, they are sufficiently specced to run keyboard, mouse, and 6k@60hz, through a single TB4 cable. So no need for DP, no need for DSC, no need for flaky kernel upgrade.

I haven't tried the splash screen yet tho :o