aight check this on the tupac site.....scrool down to the dr.dre bit............it states tht this beef started when dre didnt show for snoops trial....its a fact he didnt show........but pac was also mad tht dre hadnt dropped an album for so long and wasnt doing much...............so it was both reasons.........but the main reason is tht dre no-showed to snoops trial..................nuff said on this subject nah........
http://www.2pacplanet.com/adversaries.php