The May 2005 revision of the iMac G5 got a 200 MHz speed boost, bringing it to 1.8 GHz and 2.0 GHz. Other improvements include an 8x dual-layer SuperDrive, better video, gigabit ethernet, and an ambient light sensor (ALS).
Where did the computer go? It’s behind the flat panel display in the iMac G5! And the mouse and keyboard are available as wireless models with Bluetooth (which remains optional and can only be installed at the factory) – that means less cable clutter than most users are used to.