Some beeping AFTER the computer is shutdowned

[honn]

My computer beeps AFTER shutdown is successfully initiated:

- The computer would normally go through the shutdown process,

- After it shutdowned (the screen turned black, the desktop lights off, the fan's no longer powered), immediately the computer booted itself again, and immediately beeped with two long beeps and two short beeps along with corresponding blinking of the power light. 

- It would beep for a minute or so, then stayed blinking throughout until I had to manually shut it down. 

Note: If I turn on the computer normally after the hard shut down, it would boot up fine, although the time it takes from the Windows loading page to the Desktop is quite a bit slower than regular. 

Please help! 

Thanks a lot guys.  

[itsmyname]

Yes, that "hard shutdown" can cause the next start-up of Windows to do a "check-disk" process, to verify that the disk-drive is not logically corrupted.  That can take extra elapsed time.

I have no advice on why the "shutdown" command does not trigger the motherboard to "power-off", other than to check your BIOS SETUP, to see if the option to automatically reboot after a power-failure is enabled.