Earlier this week, Anandtech could report that Wester Digital has finally taken the next incremental step in spinning HDD size. The WD Red series will now come in sizes of 5 and 6 TB, as will the Green series. 6 TB is accomplished using 5 platters, which is a new trend for Western Digital. As mentioned earlier, the five-platter technology was acquired from Hitachi, and we now start seeing them in NAS type WD drives. With five platters, it means each has 1.2 TB, which is shy of the 1.25 TB expected this year. It is important, since it means the 5 TB version also contains five platters, of 1 TB each, rather than 4 * 1.25 TB.
As the AnandTech article points out, WD is still using Perpendicular Magnetic Recording (PMR) technology, as in previous drives. It means that the 1.2 TB areal density should be easily compatible with the HGST seven platters helium drives. That should make 7 * 1.2 = 8.4 TB drives immediately possible. However, as marketing seems to be focused on whole integer increments only, expect 7 and 8 TB drives in this combination. That would be in line with the predictions seen here last year.
As for price, the WD Green is not yet announced. For the Red series, 5 TB will be $250, and 6 TB $300, which puts both in at 5 cents per GB. That is 39% more expensive than the cheapest Seagate 3 TB disk in the storage graphs. However, the newest and biggest drives always start at a premium for the early adopters. These new drives will probably mean that the previous step, 4 TB, will rise to the top as the best GB per buck.