Apple will upgrade its Titanium PowerBook G4 in a few weeks' time with a model based on the PowerPC 7440, the low-power version of the second-generation G4-class PowerPC 7450, sources close to the company have claimed.
The change will allow Apple to offer 600MHz and 700MHz PowerBooks in place of the 400MHz and 500MHz machines it is currently offering. Today's PowerBooks are based on the PowerPC 7410, which supports a 100MHz frontside bus, operates at 1.8V and can handle up to 1MB of external L2 cache over a dedicated 200MHz bus. Both machines offer that full megabyte of cache.
The 7440 operates over a 133MHz bus, and its 256KB of L2 cache is integrated onto the processor die to operate at the chip's full speed. It runs at a lower voltage (1.5V) than the 7410, but consumers more than twice the power than its predecessor: 13.4W (typical) at 700MHz, compared to the 7410's 6W (typical) at 500MHz.
That will almost certainly affect the portable's thermal characteristics, and it will be interesting to see how the machine's titanium shell - already used as part of the current PowerBook's heat dissipation system - copes with the extra heat.
Ditto the battery, with the 7440's extra power consumption. Apple claims the PowerBook battery will currently operate for five hours, so it will need more advanced power management and battery technology if it's to match that figure with the new CPU.
If it fails, it may not matter too much, since our source implies the new chip is simply being used to speed-bump the PowerBook before completely new models - described as a "big revision" - are launched next year at Macworld Expo Tokyo, the traditional venue of Apple's PowerBook announcements.
That machine will be based on Apollo, Motorola's third-generation of G4-class PowerPC. Apollo - aka the PowerPC 7460 - is, we hear, coming off the production line and demonstrating good, early yields, up to 1.33GHz. The higher clock speed's impact on power consumption is likely to be balanced by better power management and a more compact 0.13 micron, silicon-on-insulator chip fabrication process.
Our source tells us the new PowerBooks are likely to appear towards the end of this month. Certainly some sort of upgrade is expected shortly following Apple's inventory-clearing price cuts made at the start of September. UK channel sources tell us that Apple's key distributors, Computer 2000 and Ingram, have no stocks of 400MHz or 500MHz PowerBook G4s, though both note that's due to change any day now. Nor is the complete absence of machines in any way untypical.
Then again, earlier this month a reader told us a PC World staffer had claimed the retailer's database showed the PowerBook as an end-of-life model. And stock does seem tight through the UK reseller channel. We shall see. ®