New G4 chip hits 1 GHz; Apple plans uncertain
Motorola says it will boost its G4 processor to 1 GHz and beyond, although it is unclear when or if Apple Computer will adopt the faster chips.
With the upcoming "Apollo" processor, Motorola's G4 processor family will be able to join the 1-GHz club, David Bearden, senior member of the technical staff at Motorola's Somerset Design Center, told an audience at the Microprocessor Forum taking place this week in San Jose, Calif.
"Motorola is committed to the G4 road map," he told the audience. "The Apollo takes the G4 to the 1-GHz range."
In a separate presentation, Intel said it would have 1-GHz notebook chips in the first half of 2001.
The new processor could prove to be a boon for Apple, the only major PC maker to use G4 chips. Apple fans, however, shouldn't hold their breath. The Apollo is based on the 700-MHz "V'Ger" G4 chip Motorola announced at last year's Microprocessor Forum, Bearden said. That chip has yet to hit the open market or find its way into an Apple system. Apple PCs now top out at 500 MHz. The vast majority of G4 processors are used in networking equipment, Motorola executives have said.
Apple representatives said that the company is always evaluating faster chips from Motorola and IBM, but just because one of the companies announces a faster offering does not mean that Apple will use it.
Apple's product road map has often not completely synchronized with the chip plans of IBM and Motorola, the two manufacturers of Power PC processors. When IBM first released chips based on copper, rather than aluminum, wires, there was a gap before Apple adopted them in its computers.
Cracking the 1-GHz barrier comes as a result of incorporating "silicon on insulator" (SOI) technology to the 700-MHz G4 processor described last year, Bearden said. SOI adds an extra layer of insulation that improves how electrons travel around a processor.
With SOI, PC manufacturers can shoot for higher performance or lower power consumption. Bearden, for instance, pointed out that Motorola has demonstrated a 22 percent increase in performance over identical non-SOI chips. Conversely, SOI-enabled processors consume 30 percent less power than non-SOI chips running at the same speed.
"The design will support maximum frequencies above 1 GHz," he said. "The V'Ger and the Apollo have fundamentally the same architecture...The difference is SOI."
The V'Ger and Apollo differ in a number of ways from the G4s currently found in Apple computers. The chips contain a longer, seven-stage pipeline, which serves as the processor's assembly line. Typically, longer pipelines allow chipmakers to increase chip speeds. The chips also contain 256K of secondary cache, while up to 2MB of third-level cache can be added.