Re: xrandr 1600x900 (ThinkPad X220T VGA-port) becomes 1440x900 (Samsung SyncMaster S20A300B)

[Max Nikulin <manikulin@gmail.com>]

On 20/10/2023 07:46, riveravaldez wrote:
> Certainly, but it hasn't. It has only VGA and DVI-D (Dual Link) inputs, 
> and the laptop has only DP and VGA outputs, so, VGA is the first option...

A decade ago I used a HDMI to DVI adapter plugged into the monitor (a 
case a bit larger than a DVI male connector having a HDMI slot). I would 
check if DP to DVI or DP to HDMI converters exist and have no 
compatibility issues (e.g. I have heard of bugs related to support of 
USB-C to DP chips).

Was external monitor connected and turned on when you were collecting 
logs? I assume that your monitor may report supported modes. May it 
happen that the VGA cable lacks wires related to the digital link for 
DDC communication and allowing to get EDID info?

I would try to get list of modes in a more direct way (adjust card-port 
path component)

   edid-decode /sys/class/drm/card0-eDP-1/edid

or

   parse-edid < /sys/class/drm/card0-HDMI-A-1/edid

from read-edid and edid-decode packages.

P.S. Do not neglect screws on VGA connectors.