Red Hat Bugzilla – Bug 127887
installer is unfriendly to non-DDC monitor
Last modified: 2008-05-09 13:34:25 EDT
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Description of problem:
A Sony Multiscan 15sf CRT monitor will do 1024x768 @75Hz, but it has
no DDC. During install and firstboot, the monitor is detected as
"Unprobed monitor" and there is no opportunity to override this, nor
is there a message about how to change it after installation. The
screen comes up as 800x600 instead.
Not allowing override of "Unprobed monitor" during install and/or
firstboot is an unexpected decrease in functionality. Both the
Anaconda developers and I have worked hard over the past 2 or 3 years
to get the manual choice working correctly (H&V frequencies were
swapped once; Dell Laptop screen choice was not clear; etc.). The FC1
and FC2 installers finally had good support for non-DDC monitors. Why
was this support removed?
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Fresh graphical install from CD-ROM using CRT monitor without DDC.
2. Enter X11 configuration screen of firstboot.
Actual Results: During firstboot the only choice is color depth
(hundreds, thousands, or millions of colors); there is no choice to
override "Unprobed monitor".
Expected Results: There should be a choice to override "Unprobed
monitor" by choosing from the monitor database.
If you boot the installer with the "resolution=1024x768" option and
(re)install with that, does that make any difference to the final
The plan is to add a "select monitor" button to the firstboot screen,
just haven't gotten there yet.
Replying to Comment #1 (Barry K Nathan): booting the installer with
"linux resolution=1024x768" gets a Monitor section in
/etc/X11/xorg.conf with HorizSync of 31.5 - 48.5, and a Screen section
than has 1024x768 first. Thus the screen is 1024x768 @60Hz, according
to "xrandr". In order to get @75Hz, then I copy from RHEL3 which has
HorizSync 31.0 - 64.0 (and VertRefresh of 50.0 to 120.0 instead of
40.0 - 70.0).
In addition to the feature work one useful thing the original poster
can do to get the monitor added to the database is (quoting mharris):
" All you have to do, is attach Microsoft Windows .INF
files supplied by the monitor manufacturer into a bugzilla bug
report that requests the entries be added to the database. Feel
free to attach all .INF files for all monitors of a given brand,
or of as many brands as you like, and they'll all get processed
If you could open a seperate bug against hwdata with the monitor.inf
attached that would be useful.
Sony Multiscan 15sf is already in the database -- it just doesn't have
DDC support and thus can't be automatically probed.
I've added a button to the firstboot screen in system-config-display
for monitor detection. Will appear in rawhide shortly.
*** Bug 121827 has been marked as a duplicate of this bug. ***
*** Bug 130679 has been marked as a duplicate of this bug. ***
*** Bug 114796 has been marked as a duplicate of this bug. ***