As you could see in the previous page, we measured performance using three different programs, DiskSpeed32, HD Tach and HD Tune.  On this page we will analyze the results provided by DiskSpeed32, while in the next pages we will discuss the results brought by the other two programs.

First, let’s take a look at the burst transfer rate results.

Here Western Digital VelociRaptor, Seagate Barracuda 7200.10, Seagate Barracuda 7200.11, Hitachi Deskstar P7K500 and Samsung HD322HJ achieved the same performance level. These drives were, on average, 12% faster than Western Digital Caviar SE16, 17% faster than Hitachi Deskstar T7K500, 32% faster than Western Digital RE2 and 95% faster than Western Digital Caviar SE.

Having a bigger buffer made a difference for Western Digital Caviar SE, where the SE16 (16 MB) model was 74.64% faster than the regular SE model (8 MB).

But the most import result is the average transfer rate. Here Western Digital VelociRaptor was the fastest disk, which was expected. Western Digital Caviar SE16, Samsung HD322HJ and Seagate Barracuda 7200.11 achieved the same performance level and they were only 7% and 9% slower than VelociRaptor, a disk that is four times more expensive than these models.

These three disks were, on average, 13% faster than Western Digital Caviar SE, 36% faster than Seagate Barracuda 7200.10, 44% faster than Western Digital RE2, 57% faster than Hitachi Deskstar P7K500 and 74% faster than Hitachi Deskstar T7K500.

The maximum transfer rate is achieved when the disk is reading data stored on its outer most tracks. Here the two hard drives from Hitachi achieved the highest transfer rate but their average transfer rate was lower than the one achieved by other disks because they also achieved the lowest minimum transfer rate, as we will discuss in just a bit.

Western Digital VelociRaptor, Western Digital Caviar SE16, Samsung HD322HJ and Seagate Barracuda 7200.11 achieved the same performance here, while Western Digital Caviar SE, Seagate Barracuda   7200.10 and Western Digital RE2 achieved the same performance level among themselves. The disks from the first group were, on average, 40% faster than the disks from the second group. Hitachi Deskstar T7K500 was 11% faster than the disks from the first group, while Hitachi Deskstar P7K500 was 23% faster.

The minimum transfer rate is achieved when the disk is reading data stored on its inner most tracks. As you can see, the difference between the maximum and the minimum transfer rate is huge, and that explains why is so important to defragment your hard disk drive from time to time, to ensure that data is mostly stored on the disk’s outer tracks, which provide a higher transfer rate.

Here is where you can better understand the difference between VelociRaptor and the other hard disk drives. While its burst, average and maximum transfer rates may be close to the rates achieved by other drives, its minimum transfer rate is far higher than any other drive included in our comparison. This means that VelociRaptor achieves a good performance even when reading the inner-most tracks from the hard disk drives, what doesn’t happen with other models.

Just to give you some numbers, VelociRaptor’s minimum transfer rate was 62% higher than Samsung HD322HJ’s, 101% higher than Seagate Barracuda 7200.10’s, 169% higher than Seagate Barracuda 7200.11’s, 132% higher than Western Digital Caviar SE’s and 209% higher than Western Digital Caviar SE16’s.

The hard drives from Hitachi achieved the lowest transfer rate here and this explains why even though they achieved a very high maximum transfer rate their average transfer rate wasn’t that great.