4TB desktop hard drives aren't really anything new—Western Digital released one last November. Seagate's new 4TB Desktop HDD.15 is a little different, however. It achieves that same capacity using four platters rather than five, and its platters spin at 5,900 RPM instead of 7,200 RPM like the 4TB WD Black.
Thanks to the reduced spindle speed and platter count, Seagate touts power savings of 35% over the competition. The company claims its drive delivers the "highest average data rate on the market today," as well: 146MB/s. Other key specs—a 64MB cache, a 6Gbps Serial ATA interface, and a 3.5" form factor—are in line with the competition.
Now, given that WD quotes (PDF) a "sustained" transfer rate of 154MB/s for its 4TB Black drive, I'm not sure Seagate's performance claim checks out. The Desktop HDD.15 does appear to have lower power draw, though: it draws only 7.5W during "typical operation" and 5W at idle, compared to 10.4W during read/write operations and 8.1W at idle for the Black.
Speaking of e-tail listings, it looks like the 4TB Desktop HDD.15 has been available for some time. The earliest Newegg reviews for it date back to late February. Yet strangely, Seagate wrote to us yesterday, "Today, Seagate will begin shipping the industry’s only 4TB/4 disk desktop solution with 1TB/platter, the Seagate 4TB Desktop HDD." Curious. We've asked Seagate to clarify and are awaiting a reply.