Seagate recently launched the 2.5-inch ultra-thin mechanical hard disk series. The hard disk of this series is only 5mm thick (traditional hard disk is mostly 7mm), weighs only 3.3oz, and has a maximum capacity of 500GB. It is expected to start retail at the end of this summer. The 500GB version will sell for $89. However, according to Dell, Lenovo and other PC manufacturers, there are