24 Dec
2015
24 Dec
'15
2:40 a.m.
I've NEVER EVER needed to put any modeline in any
distro's xorg.conf,
and I do a LOT of testing with different distro versions, Xorg
versions, CRT and LCD displays, gfxchips and video drivers. Xorg
calculates the modelines it needs if it has any valid data about the
hardware. Usually EDID is sufficient. When not (e.g. invalid EDID),
all it needs is the display's HorizSync and VertRefresh ranges, and
the desired resolution.
Well, not always. I found some combinations of displays and vieo cards
making the system not read EDID/DDC.
The rule is: If there is any problem with DDC/EDID, go with modelines.
Another good thing with modelines is that if you have monitor with
proprietary software to move and resize screen, you can compensate
lack of it using modeline.
An example of DDC incompatibility problem is Cordata monitor (800x600
only) and GeForce FX 5200. It starts with 1280x1024 resolution.
If monitor is connected to my notebook (Intel 950), it is detected
properly. If another monitor is connected to GeForce, everything is OK.
Only this single particular combination, Cordata connected to GeForce,
doesn't work.
MCbx