BikkelZ schrijft: "The Register heeft nieuws over de Motorola G4+, die dankzij langere pipelines wél de 'magische' barriere van 500 MHz weet te doorbreken. Dankzij on-die cache, 3 extra Altivec eenheden en 2 extra integer units wordt de klok-voor-klok performance van de G4 verder opgekrikt. De G4+ begint vanaf 700 MHz. De G5 wordt volgens dit artikel de eerste multi-core processor en bevat 4 G4+ cores op één die. De cores delen de cache":
The chip is essentially about getting the PowerPC's clock speed up to counter the developments Intel and AMD have made - so much for the limitations of Cisc technology, ahem. So the new chip will feature a longer instruction pipeline to allow the chip's clock speed to be raised without adversely impacting the chip's efficiency. To counter the reduction in the number of instructions a processor can handle per second inherent in a longer pipeline, the Motorola has increased the number of instruction processing units in the chip, with three extra AltiVec engines and two more integer units.
The chip's L2 cache will be brought onto the die, to allow CPU and cache to communicate at the same speed. The L2 connects to the L1 across a new, 256-bit bus. The 'G4 Plus' will support external, backside configuration L3 cache, up to 2MB of it.
That schedule suggests Apple will be pretty much stuck with its current range of dual-CPU Power Macs for some time to come. Short of upping the clock speed to 600MHz, there's little Apple can do until the 'G4 Plus' arrives. And it doesn't want to be stuck with a dual 500MHz G4 that's faster than a single-CPU 'G4 Plus' machine - remember, in the computer biz, newest is always best.
The schedule may also affect Motorola's G5 chip, its first multi-core CPU, which is believed to contain four G4s operating in close harmony to generate four times the performance of a single chip at a given clock speed. With the cores so tightly coupled, users should get all the benefit of four-way multiprocessing without the usual CPU management overhead - what, in other words, stops the new dual-CPU Power Mac G4s from delivering double the performance of a single-CPU Mac.