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External Hard Drives

Now that Vista Release Candidate 1 is available, it's time to start playing with it. I'm tired of using my current legacy operating system. Testing Vista probably means I'll probably be booting from an external hard drive.


External drives have been available in Firewire and USB flavors for years. An even better option is to route your internal SATA connectors to the back of your PC and plug in the external hard drive using its native SATA interface for maximum performance.


The performance difference between USB, Firewire, and SATA can be dramatic. Compare these throughput numbers:

SATA II55 MB/sec
SATA54 MB/sec
IDE54 MB/sec
Firewire 80041 MB/sec
USB 2.035 MB/sec
Firewire 40029 MB/sec

It's also possible to use plain old internal SATA connectors to connect external drives, but most external brackets convert the internal SATA connectors to External SATA connectors or "eSATA". These are basically just more robust, better shielded versions of regular SATA connectors. Do be careful which connector you get, because they have different shapes and aren't interchangeable.

eSATA connections are great for desktops, but most PC laptops typically only have USB connectors. Fortunately, there are enclosures that offer the best of both worlds-- USB 2.0 and SATA connections for 2.5" notebook hard drives, as well as 3.5" desktop hard drives. Just buy the enclosure and add a hard drive of your choice.

If you want maximum performance from your external drive, I recommend choosing something from the 10,000 RPM Western Digital Raptor series. I've switched to Raptors as my system drive on both my work and home PC, and the difference is quite noticeable. They're also much quieter and cooler than I expected for such fast drives. The Raptors aren't cheap, but you'll see the value of these drives the first time you boot up.

Written by Jeff Atwood

Indoor enthusiast. Co-founder of Stack Overflow and Discourse. Disclaimer: I have no idea what I'm talking about. Find me here: