Ozz,
All of the advice above is good. Have you checked to see if it might be going into standby or hibernation mode? It can look very dead and appear to be off when it goes into either of these modes.
Try this:
Rt-click on the desktop
Click Properties | Screen Saver | Power |
Under power schemes you can setup the time scheme under “plugged-in” or “batteries”.
Here is a picture of how mine works.
When leaving the computer, I just hit the (Fn & Stand by on the keyboard) to shortcut into Standby mode. HP most likely has a different combination of keys to get there, but it does have that function somewhere.
Under the “Hibernate” tab, make sure you uncheck the “Enable hibernation” box. Others may disagree, but I have only found that trouble lurks behind that function.
Click Apply.
The computer then appears to be off except for a blinking light on the side, but it uses very little power. To turn it back on, I then push the power key, just as if I was turning it on. The computer comes out of standby and is instantly is ready without having to go through the cumbersome Windows startup and boot-up process.
Normally, it is a good idea to restart your computer on a daily basis.