In a prior blog entry I discussed swapping the internal drive on my MacBook Pro and how it’s performance improved.  I decided to run the same benchmark on several different external drives I have.  To keep the comparision simple, I will show graphs for only one parameter, random write.  I used Drive Genius 2 to do the benchmarking.

Internal Drive

First to repeat my internal drive performance.

Western Digital, 2.5 in, 7200 rpm, 16 mb cache, SATA II

Segate 500 Gb in my own FW 800 case

This provides the overall best performance (green bars).  The blue bars are the stock Macbook Pro hard drive.

Now for the external hard drives, listed with the best performer first.

Firewire 800 Connection

SIIG External Firewire 800 case where I installed my own Segate, 500 Gb, PATA drive

Next is Maxtor One Touch III, 500 Gb, with a Firewire 800 interface.  Note that I have had issues using these drives on a Mac and ended up tearing apart a 750 Gb since the interface no longer worked.

The my latest purchase, a Western Digital Studio Editon, 1 Tb drive, with Firewire 800.

USB 2.0 Connection

Segate 750 Gb, SATA II, 7200 rpm drive inserted in a Thermalake USB 2.0 dock.

And finally a Western Digital, 250 Gb, Passport, 2.5 in. 5400 rpm drive.

When I get a eSATA card for my computer I can do some further testing.  Many of my drives also support Firewire 400 so I could test that, but this is enough for now.

My conclusion is that Firewire 800 is a very good interface for an external drive, much faster than USB 2.0.  The difference is far more significant than one would expect considering the theoretical difference in transfer rate is 800 vs. 480.  For 3.5 in drives on FW800, the random write was more like 4 times faster than when using USB, at least in the dock I have.