[ltp] t41p - screen turns off without a reason

[Teemu Nikkilä]

Hi,

today my T41p started to behave strange, the screen turned off and there
was no way to turn it on again. I'm using the X.org driver for the ATI
graphic chip and until now I have had no problems with X or DPMS or the
system in general.

I've tried to reboot the machine several times and to run it on
runlevels 3 and 5 and it always does the same: after some random time
from fresh boot-up, the screen turns off despite user activity or
inactivity. I can continue to work (and reboot) with a remote ssh
connection to the machine.

The only difference from my previous setup is that I disabled the HPA in
BIOS and for the first time I was able to suspend to RAM, resume and go
on without the system hanging. I have been using suspend to disk this
far without problems.

I know the screen may remain black after resume, but I have
"acpi_sleep=s3_bios" in the boot options and I had no problems like this
when I first tried S3 a couple of days ago.

Any ideas are highly appreciated,
Teemu