Lines on my screen during startup

I have a Macbook Pro (2011) that was starting to have these funky horizontal lines showing up during startup (post Apple icon, pre Finder). It seemed like they were getting bigger (taking up more screen space). I ran a hardware test (Holding down Option-D during startup) and found no hardware problem, so zapped the NVRAM (PRAM on PowerPCs) (holding down the OPTION-COMMAND-P-R durings startup until you hear the chimes).

This seems to have cleared up the problem. Just thought I'd put it out there, as the Support Communities have helped me on a number of items in the past.