Laptop goes to unresponsive black blind after 30 minutes?

You can check this link whether it relates to you http://h10010.www1.hp.com/ewfrf/wc/docum…

I have a similar issue with my HP laptop and it goes into power saving mode and all for several reason it doesn't recover that I have to press the power button for a long time to power it off. I just unfit it from the power options via the control sheet.