Hi Guys, I just (about 5 minutes ago) upgraded my early 2011 macbook pro RAM from 4gb to 8gb. It seems everything went fine, my system recognizes the RAM and nothing's crashing. It's much faster then before but my question is this: I went into "About this Mac" to ensure that the system was recognizing the new RAM. It does and has all the requisite information ... but the serial number is just a bunch of zeros ... is that what it's supposed to be? How come it was able to recognize manufacturer and part number but not the serial number? BTW: I used these: http://www.amazon.com/Crucial-204-p...JQQI/ref=sr_1_1?ie=UTF8&qid=1325632549&sr=8-1 Thanks!