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Seagate's First Serial ATA Hard Drive

Seagate's fifth-generation Barracuda Serial ATA V is the company's first hard drive to use the new fangled Serial ATA connection technology. In fact, Seagate claims it's the "world's first desktop storage platform to support native Serial ATA." Announced in June of 2002, the Barracuda Serial ATA V model ST-3120023AS is actually the successor to the Barracuda ATA IV, a venerable hard drive with a reliable reputation in the mainstream, high-performance PC and entry-level server markets.

Fluid-Dynamic Bearings

Segate's SoftSonic FDB motor uses a layer of lubricant in place of the metal ball-bearings used in traditional hard drives. This is because ball-bearings are not perfectly round and have a tendency to deform over time. The metal-to-metal contact of the rotor and shaft in ball-bearing motors can cause irregularities that can have an affect on data written on the disc(s). Fluid-dynamic bearings, on the other hand, separate the rotor and the shaft with a layer of lubricant that is one-tenth the thickness of a human hair. The silky smooth fluid minimizes track spacing and allows more tracks to be written per square inch of disk space. It also increases rotational speeds for future generation Barracudas.

Serial ATA

The Barracuda SATA V comes with a native Serial ATA interface which is faster, simpler and more intelligent than the traditional Parallel ATA hard drive interface that still seems to rule the industry. In its first and current generation, Serial ATA has an interface capable of transferring 150 megabytes per second (MB/sec). While this first-generation iteration of the technology is not really much faster than the 133MB/sec Parallel ATA standard, future generations of the technology will double the 150MB/sec speed again, and again, and again. In fact, it is quite amazing how engineers continually accomplish this feat. It is incredible considering the current Ultra ATA/133 Parallel ATA standard has reached its ceiling at 133MB/sec.

Serial ATA is completely compatible with today's software while providing many architectural enhancements. Using thinner wires that connect to only 4 pins rather than the 80 pins used today, the lower voltages allow of Serial ATA cables to be up to one meter in length compared to the 18" limitation of the 40- and 80-pin Parallel ATA flat cable –- almost three times the length.

Serial ATA cables are easier to route inside a computer and provide better airflow around other parts. Also, the physical architecture change from parallel to serial means the master/slave designation is gone; the point-to-point connection of the Serial ATA interface requires each drive to be connected directly to the motherboard socket, so the days of daisy-chaining two hard drives off a single connection are history. Of course, since Serial ATA connectors are physically smaller than Parallel ATA sockets, more real estate is freed on motherboards and controller cards. The downside is most new Serial ATA equipped motherboards only come with two Serial ATA connectors, which means you are limited to just two hard drives.

GeekSpeak's Hard Drive Technologies article offers an in-depth explanation of the new Serial ATA standard. We urge you to read it as it explains how hard drives work and compares and contrasts the various hard drive connection technologies. More information can also be found in the Serial ATA - New Interface for High-Performance and Mainstream Desktop PCs article at Seagate’s website.

The Seagate SeaShell

Seagate's ingenious SeaShell packaging provides enhanced drive protection from harm during handling. Seagate claims the SeaShell can protect the drive from up to 1,000 Gs of non-operating shock.

Seagate has demonstrated the increased protection provided by the SeaShell by dropping two drives from a height of 12 inches; one was protected by the SeaShell and the other was protected by a traditional anti-static ESD bag. The ESD-wrapped drive suffered 1,000 to 1,500 Gs of force while the SeaShell-protected drive suffered only 50 to 150 Gs, which is well within a Seagate drive's shock range.

G-Force Protection

The Barracuda SATA V itself is built with some very sturdy features. Seagate dubs it, "Best-in-class non-operating shock for excellent reliability" and backs it up with a shock rating of 350 Gs non-operating shock and vibration. Seagate has a few other branded features as well including Safe Sparing technology that ensures the drive will return to the same sector after a power outage and CBDS (continuous background defect scanning) which proactively identifies and eliminates defects. It also includes full support for Enhanced S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) that predicts and prevents problems transparently before they affect the end user.

Benchmarks

The Barracuda SATA V provides an average read speed of 37.3 megabytes per second (MB/sec), which is not bad but not great either considering that newer sixth and seventh generation Barracuda drives have data transfers in the 40-55MB/sec range. This is especially true of the larger 160GB and 200GB versions. However, the 13.3ms random access time is actually pretty good for a 7,200 RPM drive of this capacity. The CPU utilization is low too.

The drive speed is always greater on the outer edges of the hard drive platter because the head, which is placed over the disc that is spinning at a constant rate of 7,200 RPM, is actually reading more data from the outer edges of the disc's circumference rather than from the inner tracks. This is why users who partition their hard drive, creating a dedicated partition for their operating system at the front of the drive are able to get more performance out of their operating system overall. It forces the files to stay in that particular partition which is located in the faster section of the hard drive.

Hard drive write speeds are always lower than the read speeds as the head is doing much more work. Of course, writing books has always taken longer to write than to read, except for people like Stephen King.

Conclusion

Overall, the Seagate Barracuda Serial ATA V is a very good drive, especially when one considers that this is Seagate's first-generation Serial ATA endeavor. With Serial ATA still in its infancy, it comes as no surprise that the Barracuda ATA V is no faster than drives using the older UltraATA standard. However, what is surprising is how far the technology has come in just over a year. With two new generations of drives available, Seagate has shown that the faster high-end speeds of the 150MB/sec Serial ATA specification is needed, especially when drives are hooked together in a RAID configuration and the data throughput of the drives is increased by the number of drives used.

Of course, first generation Serial ATA was meant to transition the industry towards a new technology, so the reigns may well be in place, limiting the drive's full potential. This is speculation. One superior aspect of Serial ATA drives is the enhanced ECC (error-correction code) that performs on-the-fly hardware correction. The thinner cables are nice too, especially for computers with faster and hotter hard drives that need better airflow. We think the Barracuda ATA V is a good buy simply because of its quiet design. When you add that with good solid performance and reliability (remember that we have been pounding on this drive for over a year), we give the Seagate Barracuda Serial ATA V hard drive a big thumbs up.

More in-depth information and specifications can be found in the Barracuda ATA V product manual (Requires Adobe Acrobat .PDF viewer to read). The drive comes with a one-year limited warranty.

Specifications