I’ve just purchased a new SATA-based external hard drive to use with demos and I thought I would share some details about the performance gain over my older ATA-based hard disk.

I’ve been doing a few demonstrations of Microsoft SoftGrid using VMware Workstation on my laptop with an external USB attached hard drive and I’ve also got a couple of user group presentations coming up. So I wanted to squeeze some better disk performance out of this setup because every second counts during demos.

Before I read Mark’s post about USB attached hard drive performance in his notebook, I was hoping to add a second internal hard drive to my Dell laptop, but unfortunately Dell doesn’t provide a media bay type disk enclosure for this model. I was looking into using Firewire until I considered eSATA. I found this review of the Belkin SATA ExpressCard very useful when looking at what I might expect from eSATA.

Here’s what I ended up ordering:

To power this drive I have to connect the included USB power lead. I’m not sure if I used a better quality eSATA cable that it would provide enough power, but carrying the extra cable is not too much of a hassle. I’ve performed these tests on my laptop which has the following hardware:

  • Dell Vostro 1400
  • Intel Core 2 Duo (2.2GHz, 4MB Cache)
  • 4GB RAM
  • Windows Vista x64

To test the performance of my disk setup, I’ve used HD Tune because they offer a free version and it’s easy to use. I tested the performance of my original hard disk (Seagate Momentus 5400.3 80GB ATA/100 5400RPM 16MB 2.5”) connected to this laptop via USB. The result stays consistent right up until the end of the test:

Orignal disk performance over USB

When I performed the same test on a desktop machine the throughput was about 5MBps higher and was consistent to 100%. This is the performance of the new hard disk over a USB connection:

New disk performance over USB

And the performance of the same hard disk over an eSATA connection using the Belkin ExpressCard:

New disk performance over eSATA

Overall I’m pretty happy with the performance of the new disk. It more than doubles the performance of my older disk yet still in a portable package and my VMs feel much much snappier.

  Original (USB) New SATA (USB) New SATA (eSATA)
Minimum transfer rate 21.4MBps 27.8MBps 33.7MBps
Maximum transfer rate 25.2MBps 29.5MBps 65.4MBps
Average transfer rate 24.8MBps 29.2MBps 52.3MBps
Access time 16.5ms 15.1ms 14.6ms
Burst rate 19.6MBps 22.9MBps 75.1MBps
CPU utilisation 13.6% 17.1% 3.4%