Switched from Nvidia 1070 to AMD Radeon 6650XT GPU and 2nd monitor won't detect available resolutions

Hi, first post. Hope I’ve included the correct information, I’m tryin!

I just switched my nvidia 1070 to a Radeon 6650 XT after struggling with nvidia for years. The final straw was my nvidia-settings disappeared from my system this morning and I couldn’t configure my screens to properly do my work. I was writing a post earlier trying to troubleshoot my nvidia problems but ended up throwing in the towel and picking up this 6650 on a good deal.

Everything seems great with the new card except my 2nd monitor (out of 3) is stuck at a 640*480 resolution. The monitor had no problem being recognized as a 1440p / 140hz screen when using the nvidia card with the same cable. It also has no problem detecting if I boot into windows with my current hardware configuration / cables.

The screen in question is hooked up over Display Port. I don’t remember the exact version of the cable, but I know I had to buy a good one to get full resolution / refresh rate out of the monitor.

I am by no means a linux expert or power user but I am trying to learn and know enough to be dangerous.

I have restarted the PC, monitor, changed physical ports, all the stupid stuff.

Here is what I’ve read so far trying to troubleshoot:

I think the problem is with the EDID not making it into Manjaro. This might not be the correct terminology, but the monitor does detect and work properly in Windows.

Here is my inxi -Fazy:

  Kernel: 6.1.22-1-MANJARO arch: x86_64 bits: 64 compiler: gcc v: 12.2.1
    parameters: BOOT_IMAGE=/boot/vmlinuz-6.1-x86_64
    root=UUID=c6eb747c-9145-49f6-899d-55e9560ef280 rw quiet apparmor=1
    security=apparmor udev.log_priority=3
  Desktop: KDE Plasma v: 5.27.3 tk: Qt v: 5.15.8 wm: kwin_x11 vt: 1 dm: SDDM
    Distro: Manjaro Linux base: Arch Linux
Machine:
  Type: Desktop Mobo: ASUSTeK model: MAXIMUS VIII HERO ALPHA v: Rev 1.xx
    serial: <superuser required> UEFI: American Megatrends v: 3504
    date: 06/30/2017
Battery:
  ID-1: hidpp_battery_0 charge: 90% condition: N/A volts: 4.1 min: N/A
    model: Logitech G Pro Wireless Gaming Mouse type: N/A serial: <filter>
    status: discharging
CPU:
  Info: model: Intel Core i7-6700K bits: 64 type: MT MCP arch: Skylake-S
    gen: core 6 level: v3 note: check built: 2015 process: Intel 14nm family: 6
    model-id: 0x5E (94) stepping: 3 microcode: 0xF0
  Topology: cpus: 1x cores: 4 tpc: 2 threads: 8 smt: enabled cache:
    L1: 256 KiB desc: d-4x32 KiB; i-4x32 KiB L2: 1024 KiB desc: 4x256 KiB
    L3: 8 MiB desc: 1x8 MiB
  Speed (MHz): avg: 3350 high: 4000 min/max: 800/4200 scaling:
    driver: intel_pstate governor: powersave cores: 1: 1200 2: 4000 3: 4000
    4: 4000 5: 1600 6: 4000 7: 4000 8: 4000 bogomips: 64026
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
  Vulnerabilities:
  Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf mitigation: PTE Inversion; VMX: conditional cache flushes, SMT
    vulnerable
  Type: mds mitigation: Clear CPU buffers; SMT vulnerable
  Type: meltdown mitigation: PTI
  Type: mmio_stale_data mitigation: Clear CPU buffers; SMT vulnerable
  Type: retbleed mitigation: IBRS
  Type: spec_store_bypass mitigation: Speculative Store Bypass disabled via
    prctl
  Type: spectre_v1 mitigation: usercopy/swapgs barriers and __user pointer
    sanitization
  Type: spectre_v2 mitigation: IBRS, IBPB: conditional, STIBP: conditional,
    RSB filling, PBRSB-eIBRS: Not affected
  Type: srbds mitigation: Microcode
  Type: tsx_async_abort mitigation: TSX disabled
Graphics:
  Device-1: AMD Navi 23 [Radeon RX 6650 XT / 6700S 6800S] vendor: ASRock
    driver: amdgpu v: kernel arch: RDNA-2 code: Navi-2x process: TSMC n7 (7nm)
    built: 2020-22 pcie: gen: 4 speed: 16 GT/s lanes: 16 ports:
    active: DP-1,DP-2,HDMI-A-1 empty: DP-3 bus-ID: 03:00.0 chip-ID: 1002:73ef
    class-ID: 0300
  Display: x11 server: X.Org v: 21.1.8 with: Xwayland v: 23.1.1
    compositor: kwin_x11 driver: X: loaded: amdgpu unloaded: modesetting,radeon
    alternate: fbdev,vesa dri: radeonsi gpu: amdgpu display-ID: :0 screens: 1
  Screen-1: 0 s-res: 4279x1920 s-dpi: 96 s-size: 1132x508mm (44.57x20.00")
    s-diag: 1241mm (48.85")
  Monitor-1: DP-1 mapped: DisplayPort-0 pos: bottom-c
    model: LG (GoldStar) ULTRAGEAR serial: <filter> built: 2021 res: 2560x1440
    hz: 144 dpi: 109 gamma: 1.2 size: 597x336mm (23.5x13.23") diag: 685mm (27")
    ratio: 16:9 modes: max: 2560x1440 min: 640x480
  Monitor-2: DP-2 mapped: DisplayPort-1 pos: bottom-r res: 640x480 hz: 60
    size: N/A modes: 640x480
  Monitor-3: HDMI-A-1 mapped: HDMI-A-0 pos: primary,top-left model: BKY1561
    serial: <filter> built: 2019 res: 1080x1920 hz: 60 dpi: 141 gamma: 1.2
    size: 194x345mm (7.64x13.58") diag: 397mm (15.6") ratio: 3:2, 16:10 modes:
    max: 1920x1080 min: 720x400
  API: OpenGL v: 4.6 Mesa 23.0.1 renderer: AMD Radeon RX 6650 XT (navi23
    LLVM 15.0.7 DRM 3.49 6.1.22-1-MANJARO) direct-render: Yes
Audio:
  Device-1: Intel 100 Series/C230 Series Family HD Audio vendor: ASUSTeK
    driver: snd_hda_intel bus-ID: 3-1:2 v: kernel chip-ID: 19f7:000a
    bus-ID: 00:1f.3 class-ID: 0300 chip-ID: 8086:a170 serial: <filter>
    class-ID: 0403
  Device-2: AMD Navi 21/23 HDMI/DP Audio driver: snd_hda_intel v: kernel
    pcie: gen: 4 speed: 16 GT/s lanes: 16 bus-ID: 03:00.1 chip-ID: 1002:ab28
    class-ID: 0403
  Device-3: RODE Microphones AI-1 type: USB
    driver: hid-generic,snd-usb-audio,usbhid
  Device-4: Logitech Logitech G PRO X Gaming Headset type: USB
    driver: hid-generic,snd-usb-audio,usbhid bus-ID: 5-1.3:5 chip-ID: 046d:0aaa
    class-ID: 0300 serial: <filter>
  API: ALSA v: k6.1.22-1-MANJARO status: kernel-api with: aoss
    type: oss-emulator tools: alsamixer,amixer
  Server-1: sndiod v: N/A status: off tools: aucat,midicat,sndioctl
  Server-2: JACK v: 1.9.22 status: off tools: N/A
  Server-3: PipeWire v: 0.3.67 status: off with: pipewire-media-session
    status: active tools: pw-cli
  Server-4: PulseAudio v: 16.1 status: active tools: pacat,pactl
Network:
  Device-1: Intel Ethernet I219-V vendor: ASUSTeK driver: e1000e v: kernel
    port: N/A bus-ID: 00:1f.6 chip-ID: 8086:15b8 class-ID: 0200
  IF: enp0s31f6 state: up speed: 1000 Mbps duplex: full mac: <filter>
  Device-2: Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter
    vendor: ASUSTeK driver: ath10k_pci v: kernel pcie: gen: 1 speed: 2.5 GT/s
    lanes: 1 bus-ID: 0c:00.0 chip-ID: 168c:003e class-ID: 0280 temp: 50.0 C
  IF: wlp12s0 state: down mac: <filter>
Bluetooth:
  Device-1: ASUSTek Qualcomm Bluetooth 4.1 type: USB driver: btusb v: 0.8
    bus-ID: 1-9:3 chip-ID: 0b05:1825 class-ID: e001
  Report: rfkill ID: hci0 rfk-id: 0 state: up address: see --recommends
Drives:
  Local Storage: total: 2.95 TiB used: 74.95 GiB (2.5%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Samsung
    model: SSD 970 EVO Plus 2TB size: 1.82 TiB block-size: physical: 512 B
    logical: 512 B speed: 31.6 Gb/s lanes: 4 type: SSD serial: <filter>
    rev: 4B2QEXM7 temp: 37.9 C scheme: GPT
  ID-2: /dev/sda maj-min: 8:0 vendor: Intel model: SSDSC2CW240A3
    size: 223.57 GiB block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s
    type: SSD serial: <filter> rev: 400i scheme: GPT
  ID-3: /dev/sdb maj-min: 8:16 vendor: Western Digital model: WDBNCE0010PNC
    size: 931.51 GiB block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s
    type: SSD serial: <filter> rev: 40RL scheme: GPT
Partition:
  ID-1: / raw-size: 1.82 TiB size: 1.79 TiB (98.37%) used: 74.95 GiB (4.1%)
    fs: ext4 dev: /dev/nvme0n1p2 maj-min: 259:2
  ID-2: /boot/efi raw-size: 300 MiB size: 299.4 MiB (99.80%)
    used: 316 KiB (0.1%) fs: vfat dev: /dev/nvme0n1p1 maj-min: 259:1
Swap:
  Alert: No swap data was found.
Sensors:
  System Temperatures: cpu: 32.0 C mobo: N/A gpu: amdgpu temp: 54.0 C
    mem: 56.0 C
  Fan Speeds (RPM): N/A gpu: amdgpu fan: 0
Info:
  Processes: 276 Uptime: 30m wakeups: 2 Memory: 62.74 GiB used: 3.6 GiB (5.7%)
  Init: systemd v: 252 default: graphical tool: systemctl Compilers:
  gcc: 12.2.1 clang: 15.0.7 Packages: 1788 pm: pacman pkgs: 1747 libs: 386
  tools: pamac,yay pm: flatpak pkgs: 24 pm: snap pkgs: 17 Shell: Zsh v: 5.9
  default: Bash v: 5.1.16 running-in: konsole inxi: 3.3.26

Here is my xrandr --props

DisplayPort-0 connected 2560x1440+1080+97 (normal left inverted right x axis y axis) 597mm x 336mm
        EDID: 
                00ffffffffffff001e6d7f5b794a0a00
                011f0104b53c22789f8cb5af4f43ab26
                0e5054254b007140818081c0a9c0b300
                d1c08100d1cf09ec00a0a0a067503020
                3a0055502100001a000000fd003090e6
                e63c010a202020202020000000fc004c
                4720554c545241474541520a000000ff
                003130314e54484d4b553432350a015b
                02031a7123090607e305c000e6060501
                60592846100403011f13565e00a0a0a0
                29503020350055502100001a5aa000a0
                a0a0465030203a005550210000006fc2
                00a0a0a0555030203a0055502100001a
                00000000000000000000000000000000
                00000000000000000000000000000000
                000000000000000000000000000000da
        _KDE_SCREEN_INDEX: 1 
        GAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        DEGAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        GAMMA_LUT: 0 
                range: (0, 65535)
        CTM: 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 
                0 1 
        DEGAMMA_LUT: 0 
                range: (0, 65535)
        TearFree: auto 
                supported: off, on, auto
        subconnector: Native 
                supported: Unknown, VGA, DVI-D, HDMI, DP, Wireless, Native
        HDCP Content Type: HDCP Type0 
                supported: HDCP Type0, HDCP Type1
        Content Protection: Undesired 
                supported: Undesired, Desired, Enabled
        vrr_capable: 1 
                range: (0, 1)
        max bpc: 8 
                range: (8, 16)
        underscan vborder: 0 
                range: (0, 128)
        underscan hborder: 0 
                range: (0, 128)
        underscan: off 
                supported: off, on, auto
        scaling mode: None 
                supported: None, Full, Center, Full aspect
        link-status: Good 
                supported: Good, Bad
        CONNECTOR_ID: 86 
                supported: 86
        non-desktop: 0 
                range: (0, 1)
   2560x1440    143.97*+ 120.00    99.95    59.95  
   1920x1200    143.97  
   1920x1080     74.98    60.00    60.00    50.00    59.94  
   1600x1200    143.97  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1440x900     143.97  
   1280x800      59.81  
   1152x864      59.97  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x480       60.00    59.94  
   640x480       75.00    60.00    59.94  
DisplayPort-1 connected 640x480+3639+97 (normal left inverted right x axis y axis) 0mm x 0mm
        _KDE_SCREEN_INDEX: 3 
        GAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        DEGAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        GAMMA_LUT: 0 
                range: (0, 65535)
        CTM: 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 
                0 1 
        DEGAMMA_LUT: 0 
                range: (0, 65535)
        TearFree: auto 
                supported: off, on, auto
        subconnector: Native 
                supported: Unknown, VGA, DVI-D, HDMI, DP, Wireless, Native
        HDCP Content Type: HDCP Type0 
                supported: HDCP Type0, HDCP Type1
        Content Protection: Undesired 
                supported: Undesired, Desired, Enabled
        vrr_capable: 0 
                range: (0, 1)
        max bpc: 8 
                range: (8, 16)
        underscan vborder: 0 
                range: (0, 128)
        underscan hborder: 0 
                range: (0, 128)
        underscan: off 
                supported: off, on, auto
        scaling mode: None 
                supported: None, Full, Center, Full aspect
        link-status: Good 
                supported: Good, Bad
        CONNECTOR_ID: 94 
                supported: 94
        non-desktop: 0 
                range: (0, 1)
   640x480       59.94* 
DisplayPort-2 disconnected (normal left inverted right x axis y axis)
        GAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        DEGAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        GAMMA_LUT: 0 
                range: (0, 65535)
        CTM: 0 
        DEGAMMA_LUT: 0 
                range: (0, 65535)
        TearFree: auto 
                supported: off, on, auto
        subconnector: Unknown 
                supported: Unknown, VGA, DVI-D, HDMI, DP, Wireless, Native
        HDCP Content Type: HDCP Type0 
                supported: HDCP Type0, HDCP Type1
        Content Protection: Undesired 
                supported: Undesired, Desired, Enabled
        vrr_capable: 0 
                range: (0, 1)
        max bpc: 8 
                range: (8, 16)
        underscan vborder: 0 
                range: (0, 128)
        underscan hborder: 0 
                range: (0, 128)
        underscan: off 
                supported: off, on, auto
        scaling mode: None 
                supported: None, Full, Center, Full aspect
        link-status: Good 
                supported: Good, Bad
        CONNECTOR_ID: 98 
                supported: 98
        non-desktop: 0 
                range: (0, 1)
HDMI-A-0 connected primary 1080x1920+0+0 left (normal left inverted right x axis y axis) 345mm x 194mm
        _KDE_SCREEN_INDEX: 2 
        EDID: 
                00ffffffffffff002613601501000000
                0b1d010380211678ea2d36a75438ae26
                0d4f54a10800d1c0b3009500818081c0
                810001010101023a801871382d40582c
                450059c21000001e000000fc00424b59
                313536310a2020202020000000fd003a
                3e1e5310000a202020202020000000ff
                00303030303030303030303030310129
                020319f148900504032309071f208301
                000066030c00100080011d007251d01e
                206e285500a05a0000001e011d00bc52
                d01e20b8285540a05a0000001e000000
                00000000000000000000000000000000
                00000000000000000000000000000000
                00000000000000000000000000000000
                00000000000000000000000000000059
        GAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        DEGAMMA_LUT_SIZE: 4096 
                range: (0, -1)
        GAMMA_LUT: 0 
                range: (0, 65535)
        CTM: 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 
                0 1 
        DEGAMMA_LUT: 0 
                range: (0, 65535)
        TearFree: auto 
                supported: off, on, auto
        HDCP Content Type: HDCP Type0 
                supported: HDCP Type0, HDCP Type1
        Content Protection: Undesired 
                supported: Undesired, Desired, Enabled
        vrr_capable: 0 
                range: (0, 1)
        max bpc: 8 
                range: (8, 16)
        underscan vborder: 0 
                range: (0, 128)
        underscan hborder: 0 
                range: (0, 128)
        underscan: off 
                supported: off, on, auto
        scaling mode: None 
                supported: None, Full, Center, Full aspect
        link-status: Good 
                supported: Good, Bad
        CONNECTOR_ID: 102 
                supported: 102
        non-desktop: 0 
                range: (0, 1)
   1920x1080     60.00*+  50.00    59.94  
   1680x1050     59.88  
   2880x480      60.00    59.94  
   1280x1024     60.02  
   1440x900      59.90  
   1280x800      59.91  
   1280x720      60.00    50.00    59.94  
   1024x768      60.00  
   800x600       60.32  
   720x480       60.00    59.94  
   640x480       60.00    59.94  
   720x400       70.08  

Any suggestion on what I should try next would be very helpful, thank you.

As linked from here:
xrandr - ArchWiki
You have the choice to try xrandr at the ‘higher level’ or try KMS at the ‘lower level’ as outlined here:
Kernel mode setting - ArchWiki
(as you note the monitor works fine under other OS then extracting EDID may provide a workable approach)