I recently wanted to clean up my system and put on a fresh install of SuSE 9.1 (the same version I had previously.) Before I put on the fresh install, ACPI worked well for me (although I had to use root access to suspend the machine.) I could suspend and resume cleanly, and the power management was excellent.
Now, I can still suspend using:
# echo -n mem > /sys/power/state
But when I bring my machine back up, it automatically shuts down again. I cannot figure out why this is. I am running the same machine, with the same kernel (2.6.5-7.111.19-default). I did recompile the kernel, but only to remove EFI support so that I could use my iPod. I don't see that as being the cause of my problem, though, and the rest of the kernel is identical. Is there any particular reason this could be happening? (Or, more importantly, any way I can fix this?)