Chosen Solution
Lately I am thinking to upgrade my iMac’s processor with a core 2 duo processor. The thing I am asking myself is following: my iMac supports max 2 gb RAM, what should I change to be able to install 4 gb RAM on it with the new processor?
Ok I finally found a way to install more than 2GB RAM to my iMac the solution is the modify the firmware of the logicboard and make him believe that it is iMac 5,1 (late 2006 core 2 duo) instead of iMac 4,1 (early 2006 core duo) the is a download available here: iMac firmware upgrade but to do this one before should upgrade the CPU of the iMac with a core 2 duo CPU (the ones from iMac 5,1). I tested it and works, this way my iMac has a maximum 3,3GB RAM :)
The Intel CPUs in a iMacs (and MacBook) are soldered to the motherboard. This reduces the height of the board/chip combo and allows them to get really thin computers. There is no way to upgrade these chips.
The website EveryMac is an excellent resource for viewing the characteristics of any stock Mac. It looks like your iMac will support a processor upgrade but i can’t find anything that addresses RAM capacity after that upgrade.
