https://bugs.freedesktop.org/show_bug.cgi?id=97730

Bug ID: 97730 Summary: Monitor not recognized after upgrading to a Radeon RX 480 Product: DRI Version: DRI git Hardware: Other OS: All Status: NEW Severity: major Priority: medium Component: DRM/AMDgpu Assignee: dri-devel@lists.freedesktop.org Reporter: damien@grassart.com

Created attachment 126413 --> https://bugs.freedesktop.org/attachment.cgi?id=126413&action=edit /sys/class/drm/card0-DP-2/edid

I upgraded my video card from a Radeon HD 8770 to a Radeon RX 480 after which my monitor stopped working. I believe it is an EDID problem since dmesg contains this repeated 4 times:

[ +0.120622] [drm:drm_edid_block_valid [drm]] *ERROR* EDID checksum is invalid, remainder is 128 [ +0.000011] Raw EDID: [ +0.000005] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000004] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000005] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000004] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000005] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000005] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000004] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ +0.000005] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

As well as:

[ +0.000005] amdgpu 0000:01:00.0: DP-2: Ignoring invalid EDID block 1. [ +0.149608] amdgpu 0000:01:00.0: No connectors reported connected with modes

xrandr shows this error message when I run it: "xrandr: Output DisplayPort-1 is not disconnected but has no modes".

I can actually get the monitor working by manually adding a mode:

$ cvt 2560 1440 # 2560x1440 59.96 Hz (CVT 3.69M9) hsync: 89.52 kHz; pclk: 312.25 MHz Modeline "2560x1440_60.00" 312.25 2560 2752 3024 3488 1440 1443 1448 1493 -hsync +vsync $ xrandr --newmode "2560x1440" 312.25 2560 2752 3024 3488 1440 1443 1448 1493 -hsync +vsync $ xrandr --addmode DisplayPort-1 2560x1440

I've attached the /sys/class/drm/card0-DP-2/edid file if that is helpful. Please let me know if I can provide anything else.