Can't power down with SuSE 9.0

I've discovered that I cannot power down my sytem, except with the power switch. I've tried halt, halt -p, shutdown, telinit 0 etc., and the result is always the same. Instead of the computer turning off or even halting, it always reboots. As I'm running this computer on a UPS, this is a critical matter. Power down worked fine on this computer, when running Red Hat 7.3. The mother board is an ASUS A&V266-E & Athlon XP 1700+ CPU. tnx jk