ASUS PG278Q edid issue on AMD GPU - Solution

Dimand · 2026-01-05 09:35:20

Posting this here as a solution to others and to learn if this was the right way to go about solving this problem from more experienced users.

Today I upgraded my GPU from a NVIDIA 1080TI to an AMD 9070XT. On reboot, all my monitors were working except for my old ASUS PG278Q that showed a black screen with a slight flicker.
Checking with:

xrandr

It could not recognise the display, defaulting to 640x480 and reporting a 0mm x 0mm display on the DP-2 output where it was plugged in.
Some searching, and it found that while this monitor works fine on an NVIDIA GPU, it does not get the correct edid on my new AMD GPU.
The correct edid file was helpfully posted online (PG278Q.bin).
https://pixeldrain.com/u/6EZi2T3i

You can check this file with this command:

edid-decode

Output:

edid-decode -c PG278Q.bin 
edid-decode (hex):

00 ff ff ff ff ff ff 00 04 69 b1 27 43 cd 00 00
26 18 01 04 a5 3c 22 78 06 4c e1 a5 58 50 a0 23
0b 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
01 01 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20
35 00 56 50 21 00 00 1a 00 00 00 ff 00 23 41 53
4e 38 6c 61 6d 52 56 65 58 64 00 00 00 fd 00 1e
96 1e d2 36 01 0a 20 20 20 20 20 20 00 00 00 fc
00 52 4f 47 20 50 47 32 37 38 51 0a 20 20 01 c5

02 03 0a 01 65 4b 04 00 01 01 5a 87 00 a0 a0 a0
3b 50 30 20 35 00 56 50 21 00 00 1a 5a a0 00 a0
a0 a0 46 50 30 20 35 00 56 50 21 00 00 1a 6f c2
00 a0 a0 a0 55 50 30 20 35 00 56 50 21 00 00 1a
74 d2 00 16 a0 a0 09 50 04 10 11 00 56 50 21 00
00 1e 1c 25 00 a0 a0 a0 11 50 30 20 35 00 56 50
21 00 00 1a 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 af

----------------

Block 0, Base EDID:
  EDID Structure Version & Revision: 1.4
  Vendor & Product Identification:
    Manufacturer: ACI
    Model: 10161
    Serial Number: 52547 (0x0000cd43)
    Made in: week 38 of 2014
  Basic Display Parameters & Features:
    Digital display
    Bits per primary color channel: 8
    DisplayPort interface
    Maximum image size: 60 cm x 34 cm
    Gamma: 2.20
    Supported color formats: RGB 4:4:4
    Default (sRGB) color space is primary color space
    First detailed timing includes the native pixel format and preferred refresh rate
  Color Characteristics:
    Red  : 0.6455, 0.3437
    Green: 0.3154, 0.6250
    Blue : 0.1396, 0.0449
    White: 0.3125, 0.3291
  Established Timings I & II: none
  Standard Timings: none
  Detailed Timing Descriptors:
    DTD 1:  2560x1440   59.950550 Hz  16:9     88.787 kHz    241.500000 MHz (598 mm x 336 mm)
                 Hfront   48 Hsync  32 Hback   80 Hpol P
                 Vfront    3 Vsync   5 Vback   33 Vpol N
    Display Product Serial Number: '#ASN8lamRVeXd'
    Display Range Limits:
      Monitor ranges (Range Limits Only): 30-150 Hz V, 30-210 kHz H, max dotclock 540 MHz
    Display Product Name: 'ROG PG278Q'
  Extension blocks: 1
Checksum: 0xc5

----------------

Block 1, CTA-861 Extension Block:
  Revision: 3
  Native detailed modes: 1
  Vendor-Specific Data Block (NVIDIA), OUI 00-04-4B:
    01 01                                           '..'
  Detailed Timing Descriptors:
    DTD 2:  2560x1440   84.983126 Hz  16:9    127.390 kHz    346.500000 MHz (598 mm x 336 mm)
                 Hfront   48 Hsync  32 Hback   80 Hpol P
                 Vfront    3 Vsync   5 Vback   51 Vpol N
    DTD 3:  2560x1440   99.946436 Hz  16:9    150.919 kHz    410.500000 MHz (598 mm x 336 mm)
                 Hfront   48 Hsync  32 Hback   80 Hpol P
                 Vfront    3 Vsync   5 Vback   62 Vpol N
    DTD 4:  2560x1440  119.997589 Hz  16:9    182.996 kHz    497.750000 MHz (598 mm x 336 mm)
                 Hfront   48 Hsync  32 Hback   80 Hpol P
                 Vfront    3 Vsync   5 Vback   77 Vpol N
    DTD 5:  2560x1440  144.002728 Hz  16:9    208.660 kHz    538.760000 MHz (598 mm x 336 mm)
                 Hfront    4 Hsync  16 Hback    2 Hpol P
                 Vfront    1 Vsync   1 Vback    7 Vpol P
    DTD 6:  2560x1440   23.971497 Hz  16:9     34.926 kHz     95.000000 MHz (598 mm x 336 mm)
                 Hfront   48 Hsync  32 Hback   80 Hpol P
                 Vfront    3 Vsync   5 Vback    9 Vpol N
Checksum: 0xaf  Unused space in Extension Block: 27 bytes

----------------

edid-decode 1.32.0

Warnings:

Block 1, CTA-861 Extension Block:
  IT Video Formats are overscanned by default, but normally this should be underscanned.
  Display Product Serial Number is set, so the Serial Number in the Base EDID should be 0.
EDID:
  Base EDID: Some timings are out of range of the Monitor Ranges:
    Vertical Freq: 23.971 - 144.003 Hz (Monitor: 30.000 - 150.000 Hz)

Failures:

Block 0, Base EDID:
  Basic Display Parameters & Features: sRGB is signaled, but the chromaticities do not match.
Block 1, CTA-861 Extension Block:
  Required 640x480p60 timings are missing in the established timings and the SVD list (VIC 1).
  Missing VCDB, needed for Set Selectable RGB Quantization to avoid interop issues.

EDID conformity: FAIL

To get this correctly loaded by the kernel on boot, I put this file here:

/usr/lib/firmware/edid/PG278Q.bin

I also specified it in /etc/mkinitcpio.conf by editing the files line to:

FILES=(/usr/lib/firmware/edid/PG278Q.bin)

Edit: Forgot to add the command to recreate the initramfs:

sudo mkinitcpio -P

Finally, since I use systemd-boot, I added this to my kernel parameter at the end of options. Make sure to change the line below to the correct GPU output from xrander. my display was on DP-2 (Display Port 2).

drm.edid_firmware=DP-2:edid/PG278Q.bin video=DP-2:e

This solved all errors when I checked dmesg after boot.

Last edited by Dimand (2026-01-05 22:36:30)

Arch Linux

#1 2026-01-05 09:35:20

ASUS PG278Q edid issue on AMD GPU - Solution

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