The announcement was made Tuesday at the Embedded Processor Forum (EPF) during the event's opening keynote speech.
Building the new Gamecube around an existing architecture such as the IBM PowerPC CPU is a key benefit for the console, an analyst said.
"Developers are able to get their games to market a lot faster, because so much code exists for the PowerPC," said Richard Doherty, Director of Research at analyst group The Envisioneering Group, in an interview after the keynote.
"This is an easy to program architecture," Dean Amini, director of advanced personal technologies for IBM, said during the keynote.
The IBM CPU, called Gekko, runs a 485MHz PowerPC processor, using 4.9 watts of electricity, Amini said. The system bus features a bandwidth of 1.3GB per second, and the chip has 256KB of L2 cache on-board.
"The principal role of Gekko is to run the game scripts and the intelligence that gives characters their personalities," Amini said.
The console will also feature a sound and graphics processor from ATI Technologies, called Flipper. The chip has 51 million transistors, about half of which are used for DRAM (dynamic RAM) and colour rendering, Tim Van Hook, a fellow at ATI, said during the keynote.
Both the ATI processor and the PowerPC processor are designed for the end user to play the games on a standard television, Doherty said. "Nintendo is going for what most people are going to play these games on, and that's television screens," he said. Competitors are getting ahead of themselves by trying to get their consoles connected to anything from high-definition televisions to computer screens, Doherty added.
Flipper contains the graphics processor, the audio digital signal processor, and the input/output processor, Van Hook said. The bulk of the processor is used in creating texturing and surfaces on the console, he added.
"The Gamecube got richer graphics to market more quickly that the competition," Doherty said.
ATI used NEC for the console's embedded DRAM, with 16MB of 80MHz DRAM for audio memory, and 24MB of main memory, Van Hook said.
The Flipper input/output processor also runs Matsushita Electric's optical disc interface to read the games, four game controller interfaces, two memory card interfaces, two high speed serial ports and a high speed parallel port, Van Hook said.
The Gamecube also features support for digital video processing, "even though it is not really targeted as the all-in-one home entertainment system," market, Van Hook said.
But all the technology in the world is not going to sell a game console by itself, Van Hook said. "It's not really a technology sell; when your kid screams that he wants a Gamecube for Christmas, its not for the Megahertz or the DRAM, it's so he can play the games."
The games are what sell consoles these days, but without a decent platform to work with, game developers can run into a dead-end, Van Hook said.
The Gamecube is due to launch in Japan on 14 September, and then in the US on 5 November, Nintendo said. Other nations will follow.