On 2011/05/27 14:56 (GMT+0200) Marc Joliet composed:
Kevin O'Gorman wrote:
...The video card is an ATI Rage XL...
I wonder which kernel version you use, because in 2.6.36/37 I was hit by a nasty
EDID parsing bug. Actually, IIRC the code for parsing EDIDs was updated to
understand more features or something, and that triggered errors that didn't
come up before because those parts of the response from the monitor were simply
ignored until then (or something like that). This lead to my own monitor not
responding for over a minute at a time (sometimes going blank in between) and
other people complained that it left theirs permanently blank.
I think this is the original bug:
https://bugs.freedesktop.org/show_bug.cgi?id=31943
which contains a workaround (with patch):
"The drm EDID checker is pretty strict about what EDIDs it will accept. Try
this patch and add drm.edid_strict=0 to your kernel command line."
For me, upgrading to 2.6.38 helped, I don't see the problem anymore (though
other people report otherwise).
*If* this is the bug, it makes me wonder why you don't see it under Ubuntu.
I suspect the *buntu installer checks to see if the video chip is supported
for KMS, and applies nomodeset to Grub's cmdline when not. No ATI Rage* chip
is supported by KMS. With such an old laptop, could be he needs both
nomodeset and drm.edid_strict=0. I have a 1400x1050 Dell laptop that uses the
r128 driver, and its EDID is definitely broken. Whether I had the black
screen problem I don't remember, but it's very possible it's what caused me
to discover the existence of drm.edid_strict=0 in order to escape from either
an 800x600 X or black screens.
--
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)
Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!
Felix Miata *** http://fm.no-ip.com/
