1280 x 800 video

[Ed Cogburn]

Derek Broughton wrote:

> After much hassle, and the suggestion from someone here to use gtf, I got
> my Dell Inspiron to display 1280 x 800 (the native resolution when I
> started it up in Windows).
> 
> However, kdm comes up in a 1280x800 _virtual_ screen, on 1024x768 physical
> pixels.  Then when I log in, I have to manually switch it to 1024x768 to
> make the physical and virtual screens match, then set it back to 1280x800
> to make it _really_ show the widescreen format.
> 
> What do I need to do to make the monitor automatically show 1280x800?


Do you have a virtual resolution setting in your xorg.conf?

A scenario where I see this could happen is you have set a virtual screen
size of 1280x800 but X is unable to actually set the 1280x800 resolution
later on, so it drops back to the first one it can, in this case 1024x768,
but the virtual screen size setting is still in effect.  Have you looked at
the Xorg log to see what error messages its showing?  Its probably
rejecting the 1280x800 resolution for some reason, and instead taking the
first one that looks good to it.

A virtual setting in the screen section is actually unnecessary, just
arrange your modes on the 'Modes' line so that the one you want is the
first one, but keep them in wrap-around, left-to-right size order so that
the Alt- +/- keys are still useful.


> Also, it seems I always had Ctrl-Alt-+ and Ctrl-Alt-- to change the
> desktop size in Debian (though, since I rarely used it, perhaps it wasn't
> always there).  How come this doesn't work in Kubuntu?


Unfortunately, I customized my config early on for high-res gtf modes, so if
ubuntu/kubuntu is doing something differently, I don't know what it would
be.  The Alt- +/- keys work fine for me, if they don't it usually means
only one resolution is being declared on the 'Modes' line.  If none of
those modes work, Xorg will simply fall back to one that it autodetected or
a VGA/VESA builtin mode, which could be the 1024x768 your seeing.

Without seeing your xorg.conf, its really hard to say anything for sure.

If it helps, below is the parts of my xorg.conf that handle the modes.  I've
truncated some stuff to prevent line breaking, and left out unrelated
stuff.  My modes section has more than 3 modes (starts at 320x240), but I'm
just using 3 here to show the size order thing.  I never specify a default
nor virtual resolution, Xorg sets those based on the first (valid) mode it
sees on the 'Modes' line in the 'Screen' section.


Section "Modes"
 Identifier "Y120 Custom Modelines"
 ...
 #1400x1080 at 120 Hz (GTF) hsync: 138.84 kHz; pclk: 269.90 MHz
 Modeline "My_1400x1080" ...
 #1600x1200 at 110 Hz (GTF) hsync: 140.58 kHz; pclk: 312.65 MHz
 Modeline "My_1600x1200" ...
 #1760x1320 at 100 Hz (GTF) hsync: 139.80 kHz; pclk: 339.99 MHz
 Modeline "My_1760x1320" ...
EndSection

Section "Monitor"
 ...
 UseModes "Y120 Custom Modelines"
EndSection

Section "Screen"
 ...
 DefaultDepth 24
 ...
 SubSection "Display"
  Depth 24
  Modes "My_1760x1320" "My_1400x1080" "My_1600x1200"
 EndSubSection
EndSection