Toggle DDR 2.0 rumoured for the new MacBook Air

Apple is reportedly moving to a new storage technology for its upcoming MacBook Air refresh, which will see the days of user upgradability gone for good: hard-soldered Toggle DDR 2.0 chips.

Currently, the ultra-slim MacBook Air uses an mSATA connector to connect the Toshiba-manufactured SSD to its motherboard. Offering a theoretical maximum throughput of 3Gb/s - upgradeable to 6Gb/s with a new controller - the mSATA port is proving popular with ultraportable manufacturers.

Officially, the mSATA SSD in a MacBook Air is sacrosanct. That hasn't stopped some enterprising types prying their units open and replacing the SSD with a more capacious version, however. Apple's next move is rumoured to be making that a lot more difficult.

According to Japanese Apple-watcher Macotakara, the company is shifting from its current mSATA technology to chips based around the Toggle DDR 2.0 JEDEC standard. These chips, based around a 19nm process size and offering a throughput of up to 400Mb/s, will be soldered directly to the motherboard.

Those of you reading carefully may wonder about the performance figure quoted above. Apple's current SSDs offer read and write speeds of over 200MB/s, more than four times the 400Mb/s - or 50MB/s - offered by Toggle DDR 2.0. Apple would be chaining multiple chips together, however, providing the performance required to match or exceed today's technology.

In the move, Apple would gain some major benefits above and beyond preventing modders from replacing their own SSDs on the cheap. Unlike conventional SDR NAND flash, Toggle DDR doesn't require a free-running clock and can operate on just 1.8 volts. The process shrink and integration of driver circuitry into the motherboard will also help Apple's new MacBook Airs shed a few more millimetres to keep up with the threat from Intel's Ultrabook concept.

With the rumoured MacBook Air refresh supposedly just around the corner, we won't have long to wait to see if Toggle DDR 2.0 makes an appearance, and whether it lives up to its promise of high performance with a minimum power draw.