Hi, I've acquired a graphite Imac SE 600 which has odd blocks of colour on the menus and windows on display also white squares which move with the mouse pointer. As there is an empty OS X folder I guess that an update has been tried without the firmware update. Currently on OS9.1 I installed the update and reset the PRAM and nothing changed. If I start-up without extensions the display has horizontal dots across the whole screen that display either side of open windows. Has anyone any ideas to solve this problem? - Ta!