Following the early successes of its of 11-inch and 13-inch ultrabooks, Acer has reportedly decided to build a brand new 15-inch ultrabook that may dramatically undercut the price of Apple’s rumored 15-inch MacBook Air. DigiTimes said Wednesday that Acer has already contracted Pegratron to build the new computer, and that the device could be priced as low as $699 — $300 cheaper than the entry-level 11-inch MacBook Air. The latest rumors suggest that Apple could be prepared to deliver its 15-inch MacBook Air to the market as soon as the first quarter next year and that the device is already in the early stages of production. It is unclear when Acer’s new ultrabook will launch.