There are two different power supplies for Mac Minis. A1103 PPC uses 85W, A1176 Intel uses 110W. Make sure you have the correct one. If so, there is a last ditch effort to remove a bad resistor on the power section of the board. I have revived 3 minis this way. This explanation is incomplete, but if you find the bad resistor and remove it, it will in fact turn on. http://forums.macrumors.com/threads/2006-mac-mini-possible-fix-for-no-power-to-logic-board.1513809/
There are two different power supplies for Mac Minis. A1103 PPC uses 85W, A1176 Intel uses 110W. Make sure you have the correct one. If so, there is a last ditch effort to remove a bad resistor on the power section of the board. I have revived 3 minis this way. This explanation is incomplete, but if you find the bad resistor and remove it, it will in fact turn on. http://forums.macrumors.com/threads/2006-mac-mini-possible-fix-for-no-power-to-logic-board.1513809/