Okay a friend just brought me their late 07 macbook that they said they had put new ram in. The only put one new stick in, the stick is 2 gigs and the old 512 stick they took out, I was looking at the computer and it was only registering 512 mbs and so I reset the PRAM, I did not have time to reseat the ram or anything but was wondering if there is anything else I could do. Is the ram perhaps incompatible, but why would it only register up to the 512 mbs?