It turns off randomly and the only thing I could do is press the Fn+LCD icon twice. It would be okay for a few minutes then it will turn off again. I am a noob and I've got no clue as to what to do. Is it a power problem (I've tried changing the setting in the power management to "never" turn off the monitor but still no change) or do I just have to tweak around something somewhere?

Also, I am getting a "critical battery" message when i do not have a battery connected.

I hope you guys can help me. Thanks in advance.