HP Compaq Presario,Presario 5116 Quick Start Manual page 42

If you're going to be away
from your computer but
want to leave the power
on, you can let your
computer go to sleep. This
process allows you to keep
programs open while
putting your computer into
a low-power state, which
saves energy. It also
enables a quick restart of
your computer when you
return to your PC.
However, some software
(such as DVD software
actively playing a DVD)
might disable the sleep
mode.
You can also wake your
computer by moving the
mouse, by clicking a mouse
button, or by pressing any of
the keyboard buttons.
E
button 1 on the keyboard and your computer
Press the Sleep
goes to sleep. Or, your computer will go to sleep automatically if
no activity occurs within 20 minutes.
E
button 1
Press the Sleep
on the keyboard and your
computer wakes up.