Power Mac G4(AGP Graphics)

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The PowerMac G4 (AGP Graphics) was a major revision of the PowerMac line. Based on the Unified logic board Architecture, the G4 AGP introduced a number of performance improvements. Improvements included AGP-based graphics, AirPort compatibility, a faster memory bus, DVD-ROM or RAM standard, an internal FireWire port, 2 separate USB buses for a combined 24 Mbs, a 2X (133 MHz) AGP slot, and up to 1.5 GB of RAM. The G4 AGP started at $2499 U.S. for the 450 MHz configuration with a 20 GB hard drive and 128 MB of RAM, and $3499 U.S. for the 500 MHz configuration with a 27 GB hard drive and 256 MB or RAM (both included internal Zip drives). There were extreme supply issues with the G4 initially, due largely to Motorola's inability to deliver the 7400 chips in adequate supply. This was further compounded by an "errata" in the initial revision of the 7400 that effectively lowered the ceiling of the chip to 450 MHz. As a result, all models of the G4 were "speed dumped" in October. The $2499 U.S. 450 MHz model was lowered in speed to 400 MHz, and the $3499 U.S. 500 MHz model was lowered to 450 MHz. The price, and all other specs were the same. A 350 MHz configuration was subsequently added to replace the similar G4 (PCI Graphics) configuration a month later, and the whole line was speed-bumped back up to 400/450/500 MHz in February 2000.