Hi folks, A quick question before I offer to help out a friend. I have two 512mb 667MHz DDR2 DIMMS from an old first generation Intel iMac. Would one of these DIMMS work in the Aluminum iMac running a single 1GB 800MHz DDR2 DIMM? Common sense tells me "No" and that this combination could cause Kernal Panics, etc with different speeds of RAM installed. However, I thought it was worth asking since I have these two DIMMS sitting here doing nothing and my mate could use the extra memory for free. Thanks to those who read and respond.