eWeek has been exposed to one such source who reckons Apple is currently testing the GigaProcessor Ultralite (GPUL) on Mac OS X-based hardware.
The GPUL is expected to be a 64-bit, multi-core chip, something Intel was banging on about earlier this week. This site here (scroll through the stupidity), having bumped into a similar source, reckons the "Mac OS X is already booting happily on Prototype Units".
Similar "sources" say GPUL will use the 0.13 micron lithography copper and silicon-on-insulator (SOI) technology like the Power4. They claim a 1GHz GPUL processor will double the performance of the current 1GHz Motorola PowerPC G4.
The chip will also support Vector/SIMD Multimedia Extensions (VMX), Vector/SIMD Multimedia eXtension (VMX), an implementation, it is mooted, of the Velocity Engine used in the PowerPC G4. µ
See also:
Apple: After Power 4, what next?
Apple could easily migrate to X86
IBM to intro 64-bit PowerPC for desktop. Hi Apple!
Might Apple ditch PowerPC for Satanic chips?