1024x768 on 13.7" screen

[Rob Mayoff]

| i have been trying to get any resolution other than the max to work (i've
| been looking to get resolutions like 320x240), and all i could get is a
| blank screen, do these screens work at lower resolutions than the max? and
| do they fill the screen? or just use less pixels?

First, make sure that your X server finds your modelines acceptable.
Run "X -probeonly :1 >out 2>&1" and look for lines like these:

(--) SVGA: Mode "320x240" needs vert refresh rate of 75.14 Hz. Deleted.
(--) SVGA: Invalid vertical timing for mode "352x280". Deleted.

Those indicate invalid modelines.  Lines like this indicate valid
modelines:

(**) SVGA: Mode "1280x1024": mode clock = 110.000
(**) SVGA: Mode "640x480": mode clock = 110.000
(**) SVGA: Mode "352x288": mode clock = 110.000
(**) SVGA: Mode "352x280": mode clock = 110.000
(**) SVGA: Mode "352x240": mode clock =  15.750
(**) SVGA: Mode "320x240": mode clock = 110.000

I've found that the only way I can get lower than 1280x1024 to show up
is by pressing Fn-F8 after the X server switches to the desired
resolution.  I've only tried the resolutions listed above.  640x480
looks great.  The others don't look so good - they aren't zoomed to fill
the screen (only pixel-doubled, not pixel-tripled or anything) and not
centered.  Possibly fiddling more with the modelines could get them
centered.  Actually, testing it again right now, I find that 352x240
doubles the pixels horizontally, but DOES quadruple them vertically,
which makes sense, because 352*2 = 704, which is more than half the
screen width, but 240*4 = 960, which is less than the screen height.
However, 320x240 fails to display anything, even though 320*4 = 1280.  Hmm.

BTW, it is possible (for me anyway) to change the X server resolution on
the fly, though others have apparently had problems. I press shift-ScrLk
(which has "NumLk" printed above it). My X server beeps, and the
NumLk LCD doesn't turn on, but I'm apparently in NumLk mode anyway
because several of my keys act as the number keypad. Then pressing
Ctrl-Alt-slash changes the resolution. I have to press Fn-F8 immediately
to make anything appear on the screen after Ctrl-Alt-slash.  I wonder if
this only works for me because I deleted the XKB stuff from my
XF86Config.

Attached is my XF86Config, which is based on Bill Mair's.  I added some
experimental modelines.  Mainly I just copied the 1280x1024 modeline and
changed the display resolution without changing the timings.  I also
copied some mode stanzas from some other XF86Config, but they don't
work.

# **********************************************************************
# *            XF68Config for IBM ThinkPad 770 X                       *
# *         XFree86 3.3.3.1 with Trident Cyber3937 DVD Patch           *
# *                      Bill Mair - 1999-03-08                        *
# **********************************************************************
#
# modified by mayoff@dqd.com

Section "Files"

	RgbPath    "/usr/X11R6/lib/X11/rgb"

	FontPath "/usr/local/lib/X11/fonts"
	FontPath "/usr/local/lib/X11/fonts/100dpi"
	FontPath "/usr/local/lib/X11/fonts/75dpi"
	FontPath "/usr/local/lib/X11/fonts/TrueType"
	FontPath "/usr/X11R6/lib/X11/fonts/misc"
	FontPath "/usr/X11R6/lib/X11/fonts/100dpi"
	FontPath "/usr/X11R6/lib/X11/fonts/75dpi"

#	FontPath   "tcp/localhost:7100"
#	FontPath   "/usr/X11R6/lib/X11/fonts/misc"

	ModulePath "/usr/X11R6/lib/modules"

EndSection

Section "Keyboard"
    Protocol	"Standard"
    AutoRepeat	250 30
EndSection

Section "Pointer"
    Protocol    "PS/2"
    Device      "/dev/psaux"
EndSection

Section "Monitor"
    Identifier  "TP770X_LCD"
    VendorName  "IBM"
    ModelName   "TP770X"
    HorizSync	30-65         # multisync
    VertRefresh 50.0-70.0
    Modeline "1280x1024"  110    1280 1328 1512 1712  1024 1025 1028 1054
    Modeline "640x480"  110    640 1328 1512 1712  480 1025 1028 1054
#    Modeline "320x240"  110    320 1328 1512 1712  240 1025 1028 1054
    Modeline "352x240"  110    352 1328 1512 1712  240 1025 1028 1054
    Modeline "352x280"  110    352 1328 1512 1712  280 1025 1028 1054
    Modeline "352x288"  110    352 1328 1512 1712  288 1025 1028 1054
#    Modeline "640x480"  25.175  640  664  760  800 480 491 493 525
#   Mode "320x240" 
#    DotClock   15.750   
#    HTimings   320 336 384 400     
#    VTimings   240 244 246 262 
#     Flags        "Doublescan"
#   EndMode 

   Mode "320x240" 
    DotClock   15.750   
    HTimings   320 368 416 432     
    VTimings   240 244 246 262 
     Flags        "Doublescan"
   EndMode 

   Mode "352x240" 
    DotClock   15.750   
    HTimings   352 368 416 432     
    VTimings   240 244 246 262 
     Flags        "Doublescan"
   EndMode 

   Mode "352x280" 
    DotClock   15.750   
    HTimings   352 368 416 432     
    VTimings   280 288 286 302 
     Flags        "Doublescan"
   EndMode 

   Mode "352x288" 
    DotClock   15.750   
    HTimings   352 368 416 432     
    VTimings   288 296 290 310 
     Flags        "Doublescan"
   EndMode 
EndSection

Section "Device"
    Identifier  "TP770X_XGA"
    VendorName  "IBM"
    BoardName   "TP770X"
    Option      "accel"
EndSection

Section "Screen"
    Driver      "svga"
    Device      "TP770X_XGA"
    Monitor     "TP770X_LCD"
    Subsection "Display"
        Depth       16
        Modes       "1280x1024" "640x480" "352x288" "352x280" "352x240" "320x240"
        ViewPort    0 0
#				Virtual 2048 2048
    EndSubsection
EndSection