In the previous post commentary on the possibility that the cause of the stripes were due to the failure of some contacts in a BGA chip.
For your several comments that I have received and commentaries have appeared in other forums, it is confirmed that the problem is the LCD panel LG / PHILIPS carrying this laptop. Nothing to do with the BGA chips on the motherboard.
The problem is due to the failure of some contacts in the upper panel. The only solution is a new replacement or a team from a scrapyard.
