I was thinking of buying an older 24" iMac (2006 C2D) and upgrading the CPU, HD and RAM. But I have a few Qs: 1. What is the fastest CPU that I could drop into this iMac? 2. I know that you could put 4GB or RAM on this machine, but it only sees 3GB, is this a limitation of the MB or CPU? 3. Finally will most SATA HD work in these systems? Thanks in advance for any info, especially from those of you that may have tried this in the past.