Currently, Western Digital is the only company with a 6 TB drive on the market, dubbed as the Ultrastar He6. This drive is a world's first in that it uses helium, is hermetically sealed, and has the largest capacity on the market. The helium-based drive was released back in November, and now Seagate is vowing to offer its own 6 TB solution this April. Unfortunately, Seagate did not provide additional details other than the drive will be marketed to the enterprise sector. Obviously, Seagate can't use the same technology that helped Western Digital cram seven platters in a standard 3.5 form factor, but it may be similar.

Seagate's solution is expected to have six platters that use Perpendicular Magnetic Recording (PMR) technology (pdf). The solution may also use Shingled Magnetic Recording (SMR) technology that would have 25 percent higher density, allowing Western Digital to offer 7.5 TB capacity in a typical 3.5-inch form factor.