My iMac is of late 2006 vintage, a white C2D 2.16Ghz 20 incher. Do I have full-speed SATA 2 3Gb/s storage speed? Or do I have something less? My friend has a 1 year old Toshiba laptop that is slow with an SSD apparently due to limitations in SATA interface. I'm thinking about going SSD or one of these new 500GB/platter HDs that have 64MB RAM cache that need fast SATA to really utilize the cache well.