Not all availabe modes for the same resolution are offered
IIyama PLT2366 - valid EDID -
00 FF FF FF FF FF FF 00 26 CD 0C 56 83 05 00 00 08 16 01 03 80 34 1D 78 2A 60 41 A6 56 4A 9C 25 12 50 54 BF EF 00 71 4F 81 40 81 80 95 00 95 0F B3 00 01 01 01 01 02 3A 80 18 71 38 2D 40 58 2C 45 00 09 25 21 00 00 1E 00 00 00 FD 00 38 4C 1E 53 11 00 0A 20 20 20 20 20 20 00 00 00 FC 00 50 4C 32 34 30 39 48 44 0A 20 20 20 20 00 00 00 FF 00 31 31 30 37 37 4D 32 32 30 31 34 31 31 01 04 02 03 1F F1 4C 01 02 03 04 05 10 11 12 13 14 1E 1F 23 09 07 01 83 01 00 00 65 03 0C 00 10 00 8C 0A D0 8A 20 E0 2D 10 10 3E 96 00 09 25 21 00 00 18 01 1D 00 72 51 D0 1E 20 6E 28 55 00 09 25 21 00 00 1E 8C 0A D0 90 20 40 31 20 0C 40 55 00 09 25 21 00 00 18 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 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4F
offers 1920x1080x60 as interlaced and progressive.
Kscreen only offers one - helpfully named "1920x1080" - which happens to be interlaced, is (EDIT: not) the monitor's default, and looks a bit shimmery, not to mention hard on the eyes.
kscreen-doctor -
Output: 70 DP2 enabled connected DisplayPort Modes: 74:1920x1080@60! 440:1920x1080@50 441:1920x1080@60 442:1680x1050@60 443:1280x1024@75 444:1280x1024@60 445:1440x900@75 446:1440x900@60 447:1280x960@60 448:1152x864@75 449:1280x720@60 450:1280x720@50 451:1280x720@60 452:1440x576@50 453:1024x768@75 454:1024x768@70 455:1024x768@60 458:800x600@75 459:800x600@60 460:800x600@56 461:720x576@50 462:720x480@60 463:720x480@60 464:640x480@75 466:640x480@67 467:640x480@60 468:640x480@60 469:720x400@70 470:1920x1080@60* 471:1920x1080@50 472:1920x1080@60 Geometry: 3840,0 1920x1080 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
shows both available, and it is possible to switch (from the automatically selected 470) using
kscreen-doctor output.DP2.mode.74
,
but the GUI seems to not offer the option; it does offer the 50hz refresh rate.
xrandr --output DP2 --mode 1920x1080
in addition to Arandr also works for changing between the modes, but puzzled as to why kscreen does not show an option to choose between interlaced and progressive.