Hello. I bought 2 x 2GB DDR2 667 Ram for my MacBook. It's MacBook 4.1, model early 2008. Mac cant boot with 2 x 2GB, work's only with 2GB + 512MB as well as new, but with second 2GB + 512MB doesn't work, Mac wont start, it just beeps 3 times and I think that means some hardware problems? That means the second 2GB is broken? I bought it two days ago and it was delivered by DHL.