The software we use for measuring hard disk drive performance, DiskSpeed32, performs really long tests, since it reads all sectors on the hard disk measuring the achieved transfer rate and plotting a graph.

Normally the hard disk transfer rate varies according to the part of the disk that is being read. The disk transfer rate is higher at the disk's edge, lowering as it approaches its center. This occurs because of the zone bit recording (ZBR): in longer tracks (the ones away from the disk center) there are more sectors and more data is read at each disk spin. Because of that, the software used shows three results: maximum transfer rate (obtained on the first disk cylinders, i.e., on the tracks located near the disk edge), minimum transfer rate (obtained on the last disk cylinders, i.e., on the most inner tracks), and average transfer rate, which is the result that we are usually interested in knowing.

Because of this effect we can also explain the need of hard disk defragging and why professional disk defrag utilities such as Norton Speed Disk allow you to move the operating system files to the beginning of the hard disk. As we explained, data stored on the beginning of the disk are read at a higher transfer rate than data stored in other sectors.

Since this software performs sequential read tests, we weren’t able to test the NCQ (Native Command Queuing) capability of Samsung SP2504C hard drive, since this feature only improves random accesses.

On the graph below you see our benchmarking results (in KB/s) and our analysis. The numbers (1) and (2) represent the hardware configuration we used, as disclaimed in the previous page.

The performance of Samsung SP2504C is the fastest hard drive we tested to date. Comparing the results obtained when it was installed on the same motherboard as the other drives, it achieved a maximum performance 27.90% greater than Western Digital WD2500 250 GB, which is a SATA-150 hard drive but with only 2 MB cache, and 75.67% greater than Maxtor DiamondMax 16 250 GB, which is a ATA-133 hard drive but rotating at 5,400 rpm and with 2 MB buffer.

As for its average transfer rate, it was 22.06% faster than Western Digital WD2500 250 GB and 75.89% faster than Maxtor DiamondMax 16 250 GB.

When we installed Samsung SP2504C on a SATA-300 motherboard, its maximum and average performances remained the same, however its minimum performance increased 82.77%, which is really amazing.

You should always keep in mind that the maximum theoretical transfer rate of the interface used to connect the hard disk drive to the PC isn’t the maximum transfer rate the hard disk drive will achieve. In our tests Samsung SP2504C achieved a maximum transfer rate around 70 MB/s even though its interface can transfer up to 300 MB/s.