I've got 2 XP2400's here, one is about a year old 0243 the newest is 0341, the older one is a TBred core but the newer one appears to be a Barton shaped core....
Weirdness going on, I'm guessing the newer one is better...
Old
AXDA2400DKV3C
AIUCB0243RPBW
Newer
AXDC2400DKV3C
AQZFA0341XPMW