Apple took longer to revise the original Power Mac G5 than most people wanted. One theory is that it took Apple time to resolve the chirping and buzzing sounds generated by the “Revision A” G5 tower, ...

inside an old Apple Mac G5. The Mac G5 case is a unit, measuring 511 x 206 x 475 mm. It's about the same size as an ATX mid-tower but with some added elements and no internal compartments.