Vertical lines on inspiron 9300 laptop lcd - Dell E173FPb 17" TFT LCD Monitor

The possible reasons for this could be;

1.)A loose connection between either the graphics card and the computer mainboard or between the Graphics Card and the Computer Monitor.
2.)Your LCD monitor has become faulty and either needs to be repaired by a technician or replaced.
3.)Your graphics card need to be cleaned, clean the gold finger contact on the card.

However in my experience I would say that the monitor has become faulty, try this monitor on another computer and if it still displays vertical lines then you know that this is the case.

If your monitor works on another computer then I would say that your computer or Graphics card is having some troubles.
Overheating plays an important role here.

Kind Regards
damnor01