Hitachi Global Storage Technologies announced on Monday that it has begun shipping 4TB desktop mechanical hard disks targeted at consumer PCs. This follows on from Seagate announcing it was releasing its own 4TB disks back in September.

The Deskstar 5K4000 (PDF) is a 3.5" form factor mechanical hard disk with a 32-megabyte cache buffer. It uses the SATA 3 6Gb/s interface, and offers a maximum areal density of 443 Gbits per square inch. The spindle speed was not published but it will likely be 5,900rpm. Also bundled is 3GB of free online cloud storage.

Hitachi GST's CoolSpin technology is also featured in the new drives, with the company stating it will offer decreased power consumption without affecting the disks' overall performance. Compared to its 7K3000 3TB unit, it offers a 28% reduction in idle power consumption. Joining that is the firm's Advanced Format feature, which increases the sector size from 512-bytes to 4096-bytes (4KB), which in turn boosts capacity and offers improvements to error correcting capabilities.

The 4TB disk will initially ship in small numbers packaged as a retail version with a price of $400. Included will be mounting screws, full instructions and drivers covering most popular operating systems in order to take advantage of the massive capacity of the disks without further hardware upgrades. A "bare" OEM drive version will arrive in the hands of OEMs and other partners around the first quarter of 2012.

The company also announced that its Touro Desk external drive will be available in January with the new 4TB capacity, in addition to its existing 3TB, 2TB and 1TB variants. The new 4TB disk model will only be available with an USB 3.0 interface, whereas the rest of the range is available in a USB 2.0 version as well. Given the size of the disk, it is understandable that they chose the newer, faster connectivity option, especially as it is becoming more commonplace on computers. The suggested retail price for that unit will be $419.99.