External Hard Drive Transfer Rates

[san333]

I purchased an external seagate hard drive (FreeAgent 500gb) The drive had two external connections USB 2.0 (480MB) and eSATA (3GB). I had to spend about $30 to buy a cable interface for a motherboard to Seagate connection. After installing the eSATA connection I saw no improvement in my data transfer rate. The USB 2.0 and the eSATA were about the same. I contacted Segate (got India) an inquired about the buffer to disk transfer speed. The tech kept quoting the Host to buffer transfer speeds. I explained I would like the disk to buffer speed, "we got disconnected" Ha!. My 2nd try a very nice lady answered and I went through the same routine, only she stayed with and finally gave me a speed of 49mb/sec, which was about right. I returned the hard drive to the dealer. I then looked into the Western digital (WD)external hard drives (My Book, Studio edition) which also has USB 2.0 and eSATA connections. I am a long time customer of WD and I notice very quickly that they don't publish the Transfer rates (Buffer to Disk) for their External Hard drives. They publish the rates for all of their internal drives.
My question is how much can an eSATA connection really improve your true data transfer rate over an USB 2.0 connection. I am pretty sure the drive does'nt increase it rpms when you make an esata connection. I sent an email to WD, Its been 3 days no answer. I would like to hear some opinions on this subject. Take care.

[mikegas]

Pls look at this spec.

Answer

eSATA bus transfer rates of up to 3.0 Gbits/sec.

Unlike USB and FireWire interfaces, eSATA does not have to translate data between the interface and the computer. This enhances data transfer speeds, while saving computer processor resources and eliminating the need for an extra off-load chip.

Of course you have to make sure that your computer is setup correctly to have that transfer rate and your eSATA cable is for 3.0 Gbits/sec.

[Chai]

Of course, provided that your eSATA is not connected to PCI bus, on your motherboard which will be the bottleneck.

[Adrian Wong]

I tried eSATA on a WD My Book. Didn't work though. No idea why. Will have to retry again later.

[Dashken]

The best thing is to get an eSATA connector that connects directly from your SATA port. eSATA is actually the same thing as SATA that we used for our HDD except that it's meant to be used for HDD enclosure, thus the 'e' for external.

Theoratically eSATA has the below benefits:-

* Up to 6 times faster than existing external storage solutions: USB 2.0, & 1394
* Robust and user friendly external connection
* High performance, cost effective expansion storage
* Up to 2 meter shielded cables and connectors

In the end, the transfer rate still depends on your HDD (read/write rate) in your HDD enclosure and the type of files you are transfering.