M5183 Power Mac G4 (PCI) – I/O Panel $10.00 Rear port panel M5183 Power Mac G4 (PCI) - I/O Panel quantity Add to cart Add to Quote Continue Shopping Category: M5183 Power Mac G3 Blue & White Description I/O or built in port panel for the Apple Power Mac G4, PCI Graphics model. Out of all the Graphite Power Mac G4 models, this is the only one that’s removeable.