While the Serial ATA (SATA) standard may still be relatively new to a lot of consumers, the new SATA II specification has already been released.  Serial ATA has speeds of up to 150 Megabytes per seconds (which is commonly seen as 1.5Gb/s on the package) while Serial ATA II has twice the speed at 300 Megabytes per second.

Today, I will be reviewing the Hitachi T7K250 hard drive.  If you aren't aware already, Hitachi previously did release the 7K250 which is nearly identical.  The main differences include the introduction of Serial ATA II in this new drive as well as denser platters.  With denser platters, it means that data is closer together on the plate, allowing data to be read faster.  This drive will be tested in Serial ATA II mode to see if there are any major advantages in performance.
 

In my previous review of a Hitachi hard drive (the 7K400), I mentioned how Hitachi's hard drives weren't really seen in retail stores.  In a short amount of time, it is now safe to say that Hitachi's hard drives are now commonly seen on hard drive shelves.  Now when I walk into stores such as Best Buy, CompUSA, etc...you can see how Hitachi has now become a major competitor in the retail sector.  I have to agree now that Hitachi does have a much larger presence than before with retailers.
 

When opening the box, the package included just the hard drive itself and a manual.  The hard drive sits right in the center between two pieces of red sponge-like foam. I was a bit disappointed that the drive did not come with an extra Serial ATA cable because I'm sure many people will need it.

The hard drive is pretty much a self-contained product, therefore, there is not much too look at physically unless the drive were pried open.  The front of the drive has the typical clean silver surface with a label indicating the serial number and some specifications of the drive.

Again, the back of the drive, looks like your typical hard drive.

This drive only uses the Serial ATA interface.  The Serial ATA interface is very small and thin compared with the IDE interface.  The back of the drive has three main things to look at.  There is a typical power connector which uses a standard Molex connector from a power supply source in your computer.  The other two connectors are Serial ATA related.  The first one is used to make the connection between your motherboard and the hard drive.  The second connector comes from a compatible power supply which provides power to the drive.  Depending on the number of spare connectors on your computer, you may choose between using a molex power connector or a serial ATA connector from the power supply.  Most users will end up using the serial ATA power connector.

With a Serial ATA hard drive, there is no need to mess with that little jumper typically seen on IDE drives that allow you to choose between master and slave configurations.  The drive will automatically determine the configuration based on your current setup and BIOS settings.

In general, it is very easy to install a Serial ATA hard drive.  Just plug in the Serial ATA connector from the motherboard to the drive and plug in the appropriate connector from the power supply.  The only complications that may occur depends on your existing computer hardware.  If you are going to mix IDE and Serial ATA, it can get a little tricky sometimes, because you will need to play around with settings and connections to let the computer choose the correct drive that you want to boot from.

Since Serial ATA will eventually phase out IDE hard drives, here are some of the benefits to keep in mind regarding Serial ATA technology (obtained from "Serial ATA Interface", Frank R. Chu, Hitachi Global Storage Technologies Senior Engineer).
-point to point connection, eliminating the Master/Slave configurations
-thinner and longer cables
-no new software drivers are necessary for Serial ATA Hard Drives
-low differential voltage signals
-interface bandwidth starting with 150Mbytes/sec
-better connector design for hot-plug, blind mate applications
-32 bits CRC error checking on all data and control information

An observation I noticed with Serial ATA hard drives is that connectors of the wires of the Serial ATA cables tend to get loose easily.  I've witnessed it on a brand new computer as well as when installing this hard drive.  This is not the fault of the product or the company itself, it is just expected when working with connectors on Serial ATA devices.
 

Here is the following configuration used to test the drive:

-Windows XP Media Center Edition
-AMD 4000+ processor
-Asus A8N-SLI motherboard
-2x EVGA Geforce 6800 GT
-SuperTalent Dual Channel DDR400 memory
 

I first used HD Tach to determine the read speed of the drive.  The drive clocked in at 125MB/s.  The speed is fairly close to the spec of 150MB/s, but obviously is nowhere near the Serial ATA II specifications.  The drive had a random access time of 12.7ms and a very low CPU utilization at 1%.  The drive had an average read speed of 55.6 MB/s.
 

SiSoft Sandra was able to affirm the scored received in HD Tach with quite similar results.  The drive had nearly the same buffered read and write speeds at 123MB/s and 122MB/s respectively.  I was very impressed with the very low 6ms access time achieved with the drive. Based on Sandra's comparative database, we can see that this drive is much faster than your typical Serial ATA 7200RPM 8MB buffered hard drive.  The average read speed was 10 megabytes faster with a speed of 40.27MB/s.  The drive was able to obtain a sequential read of 60MB/s which agrees with the 55.6MB/s obtained in HD Tach.

Although the drive was not able to make full use of the bandwidth of the Serial ATA II spec, let alone Serial ATA as well, Hitachi took a nice small step by introducing Serial ATA II in a product such as this.  This will help speed up the process of converting more and more users to Serial ATA.  The main reason is that 7200 RPM is just not enough to make full use of the 300MB/s bandwidth.  I expect Serial ATA II to make larger differences in faster drives which is more capable of providing more throughput of data.

Putting Serial ATA II aside, this drive performed admirably.  Hitachi proved with this product that this drive can go fast which is what counts.  Knowing that this drive is 250GB, this storage amount seems to be the sweet spot for most consumers, therefore, making this drive very competitive among other brands.  To this day, having put the Hitachi 7K400 through a lot of torture with tons of large file extraction and compressing as well as moving/copying, I can safely say that Hitachi's drives have been very reliable so far.

Reviewed by ronald@digitalreviews.net