After reading all the reviews, it was tough to decide which board to replace. I ended up replacing a transformer, the GE power board, the display control board, and the digitron in that order. Each board seemed to make some improvement in the brightness and touch response. But the flickering didn't stop until the digitron was replaced. Since it's operating like new, I decided to leave all three new boards in place. $650 in parts was better than the $2000+ for a new built-in microwave.