MAIN BOARD PART NUMBER TXFCB0QK001 TXFCB0QK001020X TXFCB0QK001030X G XFCB0QK001020X G XFCB0QK001030X FOR VIZIO M50-C1. There are three different part number for this TV model M50-C1 and they are not compatible and not interchangeable. Please check to see if your part number matches with the one on this item. Please order by part number only. Do NOT order by TV model number. Manufacturers produce boards which appear identical, but have different firmware installed on them for the same TV model number.