How many people are having this issue? A friend of mine has rev. c and his is totally fine, is it only affecting the new PBs? The problem seems to be with 10.3.9, does that make it a software issue? Theoretically if i would install 10.4 that should fix the problem. Those who sent there PBs to apple, what exactly did they do to fix it? Heres my biggest question, if you only had RAM in the lower slot, does the computer think that theres no ram? so is the only issue in those computers with RAM in both slots?