Dell D620 screen flickers after removing power cord

I sold a Dell Latitude D620 that intermittently would go into a terrible screen flickering or blinking when the power cord was unplugged.  If I inserted the AC adapter, it was fine.  After lots of time and headaches, the answer was to update the display driver.

It had Intel 6.14.10.4764 display driver, which was bad.

I updated it to Intel 6.14.10.4814, which worked.

I recommend going to www.dell.com/support and downloading the newest display driver from there.

Another source I found: http://www.notebookforums.com/post2616684.html