This is just a speculation, but I remember the V500 having just one 5.25" bay too. It is a microATX case but it accepts full-ATX power supplies. Maybe they accomplished that by making it taller, and decided to use the extra height to add a 5.25" bay while they were at it. If I built a microATX Duron/Tbird system, I would definitely get a V500 and stuff a nice power supply in there, if it had to be a microATX case it was in.