hi I recently bought a macbook trough craigslist.. paid 900 for a macbook pro 13" 2.53 processor 4 gig memory and 500 hard drive.. only thing is the serail number on the bottom cover is different from the about this mac.... I went to apple store they said they usually go by the about this mac serial number,, what i'm worried about is this.. what if for example the hard drive thats in the macbook right now belong to another computer and was install into mines so that it woul read all the specs that i paid for.. is that possible?? according to apple store they said the serail number on the bottom belong to a much slower computer.. a 2.4 processor 250 gig hd and 2 gig memory,,, also the hard drive was corrupt.. and as you know it i didnt get the restore cds.. called apple used the bottom serial number and they send them to me however when i tried to restore from cd it didnt let me .. had to buy a new copy of snow leopard.. once it was restored i tried installing the restore cds i got a message saying i couldn access it from that drive?? who knows ,, so how can i tell whats in my computer and is there another serail number inside rather then the bottom cover??? i want to know because i need to put extended warranty, and both serial numbers are valid for additional extended warranty.. thanks in advance.. right now computer is working perfectly,,