Inspiron 15R 5520 displays random colored lines and becomes unresponsive.
My dell inspiron 15R 5520 having radeon 7670 graphics card is as good as dead. It malfunctioned within a year of purchase. The screen randomly became blank and the keys unresponsive. Upon restarting and running the diagnostic tests, all components showed to be working fine. The dell technician came with a replacement motherboard but the problem didn't showed so he went without any repair or replacements but installed the pending windows 7 updates.
The present situation- The same problem came back as I started to use it as my primary laptop. The situation got worse now I could see all sort of colored lines before the screen goes blank and the laptop gets unresponsive. The system fails even before the diagnostic test is complete.