[Cube] a mind of its onw?!

[gladys pérez-almiroty]

hi to all:
i have just found out that my cube is possessed, or as a mind of its  
own.  it turns on by itself aprox 2 minutes after i turn it off. i  
have tried the power button, the monitor button and the shut down  
command and it still turns on. at the moment what i am doing is  
turning it off - any of the above mentioned ways work- and when it  
shuts down i turn the battery off.
any ideas of what could be causing this? it has not been moved since  
the video card scare, but i was planning on upgrading the processor  
with a gigadesign i got the the mac store.
help me please, please!
g