Hi,
I'm trying to help a friend who has a DELL PP25L laptop she got it from her brother .It was purchased around 2011 with Vista if I remember correctly. I recently did a complete re-install of Windows8 and the laptop ran fine with it for a while. But now my friend is getting errors of horizontal colored line across the screen, and sometimes screen going dark, she has to restart frequently but the problems got worse and she is almost unable to use it. What can I do ? I did run the DELL diagnostic but that did not detect a problem. We checked if Windows 8 had the latest update and we have Defender anti-virus up to date. Can somebody help determining if this is a HW or SW problem ?

Please help.
Thanks!

I didn't find the right solution from the Internet.

References:
en.community.dell.com/support-forums/sof...os/f/3524/t/20015217

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