Western Digital has a new hard drive for the server crowd. The simply named XE crams up to 900GB of mechanical storage into a 2.5" form factor. Like WD's similarly sized VelociRaptor, the XE has a 10,000-RPM spindle speed. However, this drive trades the VelociRaptor's Serial ATA interface for enterprise-friendly Serial Attached SCSI connectivity. The 6Gbps SAS implementation is of the dual-port, full-duplex variety.
The XE is targeted at data centers, and WD has integrated Rotary Acceleration Feed Forward (RAFF) tech to help the drive maintain consistent performance in tightly packed servers. This RAFF mojo compensates for the vibration of adjacent drives, and it's a feature shared with the VelociRaptor. Another hand-me-down from the VelociRaptor is the optional 3.5" sled, which allows the XE to slip into enclosures with larger bays.
Somewhat surprisingly, the XE doesn't match the latest VelociRaptor's terabyte capacity. It does, however, have a slightly higher sequential transfer rate—204MB/s versus 200MB/s. WD's press release claims this sequential throughput is similar to what's offered by 3.5", 15k-RPM SCSI drives. The XE purportedly consumes up to 67% less power than its larger rivals, though.
Solid-state drives offer better performance with lower power consumption, of course, but the XE isn't really designed to take them on. WD is pushing the XE as a solution for datacenters looking to replace 3.5" mechanical storage. A five-year warranty is standard, and the prices are predictably steep. The 300, 600, and 900GB XE drives are already selling online for $195, $367, and $468, respectively. Meanwhile, the VelociRaptor 1TB can be had only $230.