Poweroff works intermittently

Nico
2004-03-30T12:58:56Z

Hi,
I'm having a strange problem with vanilla kernels 2.6.[124] on my Abit
IC7 motherboard:
halt doesn't always shut down the system, instead it hangs after having
written "entering sleep state s5"
on the console.
Acpi is enabled and recognized at boot.
There isn't a repeatable pattern for the poweroff failure: sometimes it
works after a cold boot, sometimes
after windows resets the pc, sometimes it doesn't work for days;
I also added the most recent patches to the kernel, but without
improvements.

For the record: windows always shuts down the pc properly, and I never
installed any additional driver.

What can I do?
Thanks,
Nico