[Peter]

A customer, after running a benchmark in his server's drive, got a 70MBs/sec benchmark. He was asking why this is since it was supposed to be 150 for SATA.

This is a major confusion created in part by the marketing departments of hard drive manufacturers. The SATA1 specification allows for a MAXIMUM transfer rate of 1.5 gigabits per second (Gbps, or 150MBs), however, no mechanical hard drive in the world can achieve such a transfer rate.

The SATA 2 specification allows for transfer rates of up to 3.0Gbps, and a newer specification allows for up to 6Gbps.

However, again, no mechanical device could achieve such transfer capacities. I believe the fastest drive out there is probably Western Digital's 300GB Raptor running at 10K RPM. Benchmarks show a average data transfer of 80 to 90MB/sec, with burst rates achieved to up to 160MBs/sec. These are available for your dedicated server if you so desire one. It actually beats out 15K drives due to the fact that the platters inside this drive are smaller, thus, the magnetic reader inside travels less distance when looking for data. Rumors show that Western Digital will soon be releasing the world's first 20K RPM drive using this same technology. We here are of course anxiously waiting for it

SSDs (solid state drives) however could achieve such speeds in the near future. They are basically a hard drive that uses flash memory for storage, just like a regular USB flash drive or your digital camera's card.

Such drives unfortunately are still very expensive, in the $400 range for just 32GBs of space, and they are still not very reliable. Fortunately, within a few years, they will become the norm and the speed of your average computer's drive will increase dramatically. Not to mention that it will reduce the heat produced by a server (very important for us), and its noise factor.