Tonight, I've upgraded my Blade 100 to lenny. Everything
went smoothly except X.org. With the new packages and the old
config file, the image was out of sync (one sees a flickering
mess). After three hours of playing with monitor frequency
settings, I had to start thinking. The problem was, the settings
fbset -x worked fine on the console. So
it had to be the graphics card (years of stable X drivers seem to
make one forget about that option).
/var/log/Xorg.0.log contained the following
(--) MACH64(0): Reference clock 157.5/11 (14.318) MHz. (II) MACH64(0): If modes do not work on Ultra 5/10 or Blade 100/150, set option "reference_clock" to "28.636 MHz" or "29.5 MHz"
Option "reference_clock" "29.5 MHz" in
Section "Device" of
solved the issue. Googling for reference_clock does
retrieve some pages that also mention Blade 100 and even
GDM-20D10. I had not been able to find any of them before having
reference_clock since all my queries
contained gdm 20d10 and never blade 100, and I
never looked beyond the first ten results. Using gdm 20d10
"out of sync" or blade 100 out of sync would have
retrieved some relevant results (like this
on the first page. Skimming through more results (especially if
there are less than 100 in total) would have also saved time even
with an imperfect query.