I have Dell 600m with a Radeon Mobility 9000M video card. I am posting this here because my BIOS will not POST the video card upon S3 resume, so this is instead accomplished by a gentoo patch to the radeon driver. Maybe someone here will be able to figure out what the heck is going on.
Basically, on kernel 2.6.12 and up (right now I am on 2.6.15) the machine will lock up (no HD activity, no backlight, nothing) during resume from S3 suspend. On kernel 2.6.11, this does not happen - the machine can go on suspending/resuming for months without problems. However, 2.6.15, it locks up during resume about once a week.
There is more detail and lspci output, etc, on Kernel Bug 5555:
I doubt the radeon patch is to blame for this, but you never know. Does anyone have a clue as to why this is happening?
Will watch upstream bug
bug closed upstream due to inactivity