Hello everyone, I have got a 2010 iMac and it has 2x2GB samsung PC3-10600S-09-10-F2 (1333mhz DDR SODIMM) memory in it. Now I want to upgrade to 8GB of memory and I know there are many types of memory that will fit like some kingston modules and some hynix modules for example. However I do want to put the samsung memory in it because I already have it now (it looks nice to me). Now I was doing a little research and I found there are samsung SODIMMs (1333mhz) which have a little different type numbers. -PC3-10600S-09-10-ZZZ -PC3-10600S-09-11-B2 The PC3-10600S-09-11-B2 memory has been used in some 2011 MBP's. But now I want to know what is the difference in the ram modules because the numbers are different but all are 1333mhz... Anyone? Thanks!