The current mode selection process does not select an adequate mode
with adequate timing data without a config file. Details:
(a) Use of monitor probed data (or EDID data), if available, is
only limited to deriving min/max vertical and horizontal rates.
These rates are used during validation process.
* Mode names defined in standard and detailed timing sectors
are not used. During auto-config, the most satisfactory mode
(mode with largest mode size the monitor supports) is not
guaranteed.
* Detailed timing data for modes the monitor supports is not
used. Some monitors use timing data that deviate from those
defined in default database xf86DefaultModes[]. During
auto-config, these privately defined EDID timing data can
not be taken advantage of.
(b) Solely depend on drivers to do monitor probing. Most drivers
use DDC2 probing which has an advantage of being able to probe
separate monitors when multiple monitors are connected to
a single graphics card. However it sometimes fails on some CRT
monitors and vga port connected LCD monitors.