After shutting down, do you see any messages on the screen? Does the screen go blank? What exactly do you see?
Are you using the standard shutdown process by clicking on Start-Shutdown, etc.? If that's the situation, there are a couple of possibilities that I've come across. First, I've seen such a thing happen when the CMOS battery needed to be replaced. Occasionally, when the CMOS battery needs replacement, the startup/shutdown settings are NOT saved correctly and as a result, the computer doesn't stop like it's supposed to. The CMOS battery is about the size of a nickel, costs only about $5 and can be replaced easily. See the link below for instructions with pictures:
How To Replace The CMOS Battery In Your PC(Procedures and Pictures)
The instance occurs when the power supply or on/off switch have failed...What happens if you hold the on/off button for 10-15 seconds? Does everything shut down correctly?
Hope this helps and let us know more.
I have a pavilion 6545c that has windows 98 that has been upgraded to windows ME. Whenever I shutdown the computer both cpu fan and power supply fan stay on all the time. I have checked the power settings and that does not seem to be the problem. I have also gone into the Bios and reset it to the default. What could be keeping my fans on all the time? mtnbikerone