Red Hat Bugzilla – Bug 21364
Text Mode Setup gives wrong screen resolution
Last modified: 2007-04-18 12:30:02 EDT
When installing RedHat 7.0 on a laptop (Gateway Solo 5150), with a 1024*768 generic LCD screen, the X configuration is set incorrectly, giving the wrong screen resolution (dpi). This causes applications using scaleable fonts to fail completely. The program xdpyinfo returns 10*7 dots per inch. It should be 90*90 - or even 100*100, depending on the actual screen size. At 10*7, programs like Lyx, Ghostview, and certain KDE2.0 system programs will not be able to display any readable screen fonts! This problem did not occur in RH6.0, and is presumably a bug in the new X86 installer. Another problem is that when I enter the name of the component into Bugzilla - which is Text Mode Setup Utility 1.5 - Bugzilla refuses to accept this name.
Please cut-and-paste your XF86Config-4 file. What display hardware is this (Graphics chipset)?
closed due to lack of additional feedback. Sounds like a hardware problem -- XFree 4 and higher trust the hardware to return their correct physical dimensions via DDC so that proper DPI can be set.
This bug may be a hardware problem, but the final result on my laptop is an apparent screen resolution of 10 dpi, when it should be 100. An obvious resolution would be if Xconfigurator simply requests the installer to confirm or correct the resolution. When this problem occurs - which is still present in REDHAT 7.1 - you will break the KDE login, and find the buttons unreadable, as well as the installed fonts. Other broken applications include ghostview, which also uses the dpi information. A manual fix for those people who find this problem, is to manually edit the X command where X is started, inserting the command X -dpi 100x100 in the last line of the system configurations file /etc/X11/xdm/Xservers! For gdm you have to edit the file: /etc/X11/gdm/gdm.conf and modify the 2nd last line to say: 0=/usr/bin/X11/X -dpi 100x100 or whatever dpi values are appropriate.
My laptop video chip is the Neomagic MagicMedia 256AV (NMG5) with 2.5MB Sdram, and the screen-size is 14.1''.