Ubuntu 22.04: Display port works in Mirror mode but not Extended mode

When trying to connect a Dell P2213t via Display port to the computer, the screen is blank during booting (it still shows Grub). Ctrl+Alt+F2 doesn't work either, but it seems the computer is booted as hard reboot prompts to disk check.

In a dual monitor setting, I see two monitors properly on the Display setting, but the Extended version results in blank on Display port (HDMI works fine), while the mirrored configuration works fine. I am wondering how I can get it to work in Extended mode?

PC Specs: Linux version 6.2.0-26-generic (buildd@bos03-amd64-042) (x86_64-linux-gnu-gcc-11 (Ubuntu 11.3.0-1ubuntu1~22.04.1) 11.3.0, GNU ld (GNU Binutils for Ubuntu) 2.38) #26~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC

Distribution: Ubuntu 22.04.3 LTS

System:
  Kernel: 6.2.0-26-generic x86_64 bits: 64 compiler: N/A Desktop: GNOME 42.9
    tk: GTK 3.24.33 wm: gnome-shell dm: GDM3 42.0
    Distro: Ubuntu 22.04.3 LTS (Jammy Jellyfish)
Machine:
  Type: Desktop System: ASUS product: N/A v: N/A serial: <superuser required>
  Mobo: ASUSTeK model: PRIME B660-PLUS D4 v: Rev 1.xx
    serial: <superuser required> UEFI: American Megatrends v: 2603
    date: 06/30/2023
CPU:
  Info: 6-core model: 12th Gen Intel Core i5-12500 bits: 64 type: MT MCP
    smt: enabled arch: Alder Lake rev: 5 cache: L1: 480 KiB L2: 7.5 MiB
    L3: 18 MiB
  Speed (MHz): avg: 2633 high: 3000 min/max: 800/5900 cores: 1: 800 2: 3000
    3: 3000 4: 3000 5: 801 6: 3000 7: 3000 8: 3000 9: 3000 10: 3000 11: 3000
    12: 3000 bogomips: 71884
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
Graphics:
  Device-1: AMD Navi 23 [Radeon RX 6600/6600 XT/6600M] vendor: ASRock
    driver: amdgpu v: kernel pcie: speed: 16 GT/s lanes: 16 ports:
    active: DP-1,HDMI-A-1 empty: DP-2,DP-3 bus-ID: 03:00.0 chip-ID: 1002:73ff
    class-ID: 0300
  Display: x11 server: X.Org v: 1.21.1.4 compositor: gnome-shell driver: X:
    loaded: modesetting gpu: amdgpu display-ID: :0 screens: 1
  Screen-1: 0 s-res: 1280x1024 s-dpi: 96 s-size: 339x271mm (13.3x10.7")
    s-diag: 434mm (17.1")
  Monitor-1: DP-1 pos: primary,1-1 model: Dell P2213 serial: <filter>
    res: 1280x1024 hz: 75 dpi: 69 size: 473x296mm (18.6x11.7")
    diag: 558mm (22") modes: max: 1680x1050 min: 720x400
  Monitor-2: HDMI-1 mapped: HDMI-A-1 pos: primary,1-1 model: Sony CPD-G520
    serial: <filter> res: 1280x1024 hz: 85 dpi: 84 size: 388x291mm (15.3x11.5")
    diag: 500mm (19.7") modes: max: 1280x1024 min: 720x400
  OpenGL:
    renderer: AMD Radeon RX 6600 (navi23 LLVM 15.0.7 DRM 3.49 6.2.0-26-generic)
    v: 4.6 Mesa 23.0.4-0ubuntu1~22.04.1 direct render: Yes
Audio:
  Device-1: Intel vendor: ASUSTeK driver: snd_hda_intel v: kernel
    bus-ID: 00:1f.3 chip-ID: 8086:7ad0 class-ID: 0403
  Device-2: AMD Navi 21 HDMI Audio [Radeon RX 6800/6800 XT / 6900 XT]
    driver: snd_hda_intel v: kernel pcie: speed: 16 GT/s lanes: 16
    bus-ID: 03:00.1 chip-ID: 1002:ab28 class-ID: 0403
  Device-3: Creative Labs Sound Core3D [Sound Blaster Recon3D / Z-Series]
    driver: snd_hda_intel v: kernel pcie: speed: 2.5 GT/s lanes: 1
    bus-ID: 08:00.0 chip-ID: 1102:0012 class-ID: 0403
  Sound Server-1: ALSA v: k6.2.0-26-generic running: yes
  Sound Server-2: PulseAudio v: 15.99.1 running: yes
  Sound Server-3: PipeWire v: 0.3.48 running: yes

randr output when mirrored:

Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 16384 x 16384
DP-1 connected primary 1280x1024+0+0 (normal left inverted right x axis y axis) 473mm x 296mm
   1680x1050     59.95 +  59.95  
   1400x1050     59.95  
   1600x900      59.95  
   1280x1024     75.02*   60.02    59.95  
   1440x900      59.95  
   1400x900      59.95  
   1280x960      59.95  
   1440x810      59.95  
   1368x768      59.95  
   1280x800      59.95    59.95  
   1152x864      75.00    59.95  
   1280x720      59.95    59.95  
   1024x768      75.03    60.00    59.95  
   960x720       59.95  
   928x696       59.95  
   896x672       59.95  
   1024x576      59.95  
   960x600       59.95  
   832x624       59.95  
   960x540       59.95  
   800x600       75.00    60.32    59.95  
   840x525       59.95  
   864x486       59.95  
   700x525       59.95  
   800x450       59.95  
   640x512       59.95  
   700x450       59.95  
   640x480       75.00    59.95    59.94  
   720x405       59.95  
   720x400       70.08  
   684x384       59.95  
   576x432       59.95  
   640x360       59.95  
   512x384       59.95  
   512x288       59.95  
   416x312       59.95  
   480x270       59.95  
   400x300       59.95  
   432x243       59.95  
   320x240       59.95  
   360x202       59.95  
   320x180       59.95  
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
HDMI-1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 388mm x 291mm
   1280x1024     85.02*+  85.02    75.02  
   1280x960      85.02  
   1280x800      85.02    85.02  
   1152x864      85.02    85.06    75.00  
   1280x720      85.02    60.00  
   1024x768      85.00    85.02    75.03    70.07    60.00  
   1024x768i     85.02  
   960x720       85.02  
   928x696       85.02  
   896x672       85.02  
   1024x576      85.02  
   960x600       85.02  
   832x624       85.02    74.55  
   960x540       85.02  
   800x600       85.06    85.02    72.19    75.00    60.32    56.25  
   840x525       85.02  
   864x486       85.02  
   700x525       85.02  
   800x450       85.02  
   640x512       85.02  
   700x450       85.02  
   640x480       85.02    75.00    72.81    66.67    59.94  
   720x405       85.02  
   720x400       87.85    85.02    70.08  
   684x384       85.02  
   640x400       85.02  
   576x432       85.02  
   640x360       85.02  
   640x350       85.02  
   512x384       85.02  
   512x384i      85.02  
   512x288       85.02  
   416x312       85.02  
   480x270       85.02  
   400x300       85.02  
   432x243       85.02  
   320x240       85.02  
   360x202       85.02  
   360x200       85.02  
   320x200       85.02  
   320x180       85.02  
   320x175       85.02