Quick workaround for MacBook black screen

A while ago a number of MacBook users noticed a pretty annoying black-screen bug on their systems, in which the computer would appear to be running but would not show any output on the display. To get around this issue, people were forced to restart their systems, losing any unsaved data.

Investigations of this bug showed the problem appeared to be rooted in the handling of the dual graphics cards in MacBook Pro models from 2010, and while Apple issued a software update to address the problem, this update did not help all who were experiencing it.