|"VDU"? I assume that is an external display? HP had many graphic chip failures in the past with laptops equipped with certain nVidia GPUs. If this is one of those the repair is a new motherboard. That might cost more than the price of a new laptop.|
After some Googling and looking at the specs of your laptop I believe it came outfitted with one of the defective GPUs.
There is a class action lawsuit over this. Google for HP class action lawsuit, or defective nVidia GPUs.