I feel very unlucky with my iMac purchase. First i pre-ordered the 4850 March 3rd and after a month of waiting i received it an i was getting the dreaded lock up. So i opted out for a replacement last week and it arrives today. I see the lock up was fixed with an EFI firmware update and was thrilled however the replacement has dead pixels which the 1 sent back did not. Its only 2 pixels but still how unlucky is that? What do you guys suggest i do? Will apple even consider another return is it even worth doing in my part?