MacBook Air: special CPU

Apple's not only pushed the envelope with the industrial design of the MacBook Air, but also pushed Intel to deliver some advanced CPU technology, according to a new report. Rather than use Intel's newly introduced 45-nm Penryn mobile chips, the company used a modified version of current 65nm mobile chips with smaller packaging. According to Anandtech, the new MacBook Air uses a specialized version of Intel's Merom-based Core 2 Duo chip, the same chip used in Apple's other laptops (and from other PC vendors); however, it appears that the chip is actually uses technology originally slated to ship with its next-generation Montevina platform later this year.

According to the report, the CPU comes in a package that was originally reserved for mobile Penryn due out in the second half of 2008 -- using the Montevina SFF Centrino platform. Intel apparently accelerated the introduction of the packaging technology specifically for Apple, the report says.

While Intel was initially coy about the technology, a follow-up email from the company notes that the MacBook Air chip is not a low-voltage chip, but a specially made version of its standard Core 2 Duo.

"The MacBook Air uses the Intel Core 2 Duo Processor and Intel 965GMS chipset with integrated Gfx using a new miniaturized package technology," Intel explained. "This new CPU and chipset allows for approximately 60 percent reduction in total footprint. The Core 2 Duo Processor TDP is 20 watts. The Macbook Air is using existing Core 2 Duo technology with a lower voltage spec in a new miniaturized packaging design. It is not a ULV processor."

Thus the CPU and chipset are both using advanced packaging technology for a smaller footprint, while still using the current generation mobile Core 2 Duo chips (perhaps to save costs associated with the newer Penryn chips). Anandtech notes that the 1.6GHz chip in the MacBook Air runs at 1.0V - 1.25V, while the 1.8GHz version runs at 1.1125V - 1.25V -- both less than the standard mobile Core 2 Duo, but more voltage than the Low Voltage chips.

"The TDP of these not-quite-low-voltage Core 2s reflects the increased voltage," Anandtech writes. "While the L7700 and L7500 have a 17W TDP, the chips used in the MacBook Air are rated at 20W." Standard mobile Core 2 Duo chips are 35W parts.

While it's unclear why Apple's chose a modified version of the Merom Core 2 Duo chip rather than standard low-voltage parts, the report says the that an avoidable side-effect may be a hotter notebook.

"The bigger concern however has nothing to do with packaging technology or operating voltages, but overall thermals. The MacBook Pro runs very hot and while the 20W TDP of the MacBook Air is significantly lower than the 35W TDP of the Pro, it's high for such a small chassis," the site notes. "We won't know for sure how hot the Air will get until it's in our hands but the SSD route seems like an even better bet now that we know a little more about what we're dealing with. Cutting down heat in that thin chassis will be very important, and moving to solid state storage is the only real option you have there."

by MacNN Staff