612-0017-B 661-4019 Inverter Board - 17inch iMac, 1.83-2.0GHz Core 2 Duo NB-3474W This is an inverter board for the 17" Intel iMac. It will work in both the early 2006 and late 2006 models. The inverter board is responsible for powering the backlight on the LCD. EEE code: V99,V9A