Hey I just thought about the fact that my old iMac Rev D has a 256 meg SO-DIMM and right now I don't have the cash to upgrade my 12 inch PB wit a 512 of DDR. So in the midterm, could I put the SD DIMM into my PowerBook, or does DDR and SD not mix well? I know the G4 experiences no benifit from the DDR RAM so it's not like I'd loose that...