It's the combination of idfferent parts that produces the problems, RAM PSU, BIOS revision all play a role. ANd not parts are 100% alike, I had problmes overclocking my E7200 on the P45 DS3L a while back that I couldn't fix, other people didn't have any. I put the CPu in another baord and hit 4GHz, dropped and E8500 into the P45 DS3L and also hit 4Ghz. Some things are just unexplainable.