Seagate Barracuda LP: ST32000542AS, 2 TB
This model was tested in our labs for our very first roundup of 2-terabyte HDDs. It is here for the sake of comparison. To remind you, this HDD has 32 megabytes of cache and a spindle rotation speed of 5900 RPM which is somewhat higher than that of other power-efficient products.
Seagate Barracuda XT: ST32000641AS, 2 TB
The Barracuda XT is yet another drive we have already tested in our earlier reviews. We take it once again because it is a large-capacity and future-proof model thanks to its SATA 600 interface and 64 megabytes of cache. According to our tests, the new interface is currently nothing more but a marketing feature, though. Moreover, SATA 600 is implemented in today’s mainboards with discrete controllers which are so far from ideal that HDDs connected to them prove to be inferior to HDDs connected to Intel’s South Bridge. We have decided not to benchmark HDDs in SATA 600 mode until the new standard is implemented in mainboard chipsets.
Seagate Constellation ES: ST31000524NS, 1 TB
We have not tested this HDD before although it was announced about one year ago. Seagate’s Constellation is the company’s new server-oriented series with a spindle rotation speed of 7200 RPM. Take note that the Constellation series includes 3.5-inch (marked with the suffix ES) as well as 2.5-inch (without “ES”) models.
Seagate has sharply separated its desktop and server HDD series, so we wonder if they are going to have different or, as it was the case with the Barracudas, similar firmware.
The Constellation ES series features 500GB platters and a maximum capacity of 2 terabytes, but the cache buffer is only 16 megabytes large. A server HDD does not need much cache, however, and does not rely much on it, especially at writing, to lower the risk of data loss. These HDDs are available with either SATA 300 (as our model) or SAS 600 interface.