Bug#268432: It has something to do with the color depth...

[Wolfgang Jeltsch <wolfgang@jeltsch.net>]

I checked the configuration of my woody xserver-s3 (which has version 3.3.6, 
of course, not 3.6 as I told you) and discovered that I use only a color 
depth of 16 there.  So the configuration of xserver-xfree86 4.3.0 was not so 
close to my woody configuration as I suggested.  Sorry.

When I change the depth to 24 under woody, xserver-s3 shows me "No valid modes 
found.".  So obviously the lack of suitable 24 bit color depth modes leads to 
the problem with sarge's xserver-xfree86.  I changed the color depth to 16 
under sarge and it worked.

Here is a complete overview of the results when trying the two different X 
servers with the color depths 16 and 24:

    xserver-s3, version 3.3.6 (woody) with color depth 16:
        works fine

    xserver-s3, version 3.3.6 (woody) with color depth 24:
        shows "No valid modes found."

    xserver-xfree86, version 4.3.0 (sarge) with color depth 16:
        works fine

    xserver-xfree86, version 4.3.0 (sarge) with color depth 24:
        sends monitor to powersave mode (or chooses a video mode, the monitor
        cannot handle)

I would say, of course, that xserver-xfree86 4.3.0 should also give an error 
message instead of sending the monitor asleep. ;-)