Laptop goes to sleep

I am running SuSE 7.3 Pro on my KDS 6380 laptop and if I walk away from the laptop and it sits for a while it goes into (I am assuming) sleep mode. When I come back to it I can't get it to come out of sleep and end up having to power it down which then makes it go thru it's analyzing during next bootup. I have checked and disable power save features in the BIOS, and I am not sure what is making it go to sleep. It doesn't seem to matter whether I have KDE running or not. How do I prevent it from going into this mode, or better, how do I get it back out of this mode when I come back to the computer. Greg Hicks