"Fluttering" lines on Display

The display has two 1-inch columns of lines that alternate on & off, "Fluttering," distorting the display with 1" black/white lines from the top to the bottom. The display on either side of the columns is normal in all other respects. When the iFixit window is open, and dragged across the two columns, the right hand column's fluttering is overwritten by the "Ask a question" content though the box around it, e.g., (red/yellow/green buttons, the top, blue iFixit toolbar, and the dock continue to flutter).

The left hand column continues to flutter, top to bottom.

My question: Is this a Display problem, needing a $700 display swap, or is it a Video circuit board problem, requiring Motherboard repair?