Gallery: ReadyBoost and flash drives

When you insert a flash drive into a USB port, Windows Vista loads a driver for it and then offers you this choice. Click the bottom option (Speed up my system) to test the device and quickly see whether it's fast enough for ReadyBoost.

If you see this dialog box, you've passed the test, and you can begin using the drive as a ReadyBoost cache immediately.

You must have at least 235MB of available space on the drive to use it as a ReaddyBoost cache. In practice, this means a 256MB device. Trying to use a smaller drive results inthis error message.

If your drive doesn't pass all performance tests, you'll see this message, If you think it's in error, you can try again, but chances are you'll see the same result.

Drill down through the pane on the left of Event Viewer (Applications and Services Logs, Microsoft, Windows, ReadyBoost, Operational) and then scroll through the list of events to see the performance rating for a device.

This older device is fast enough to use for occasional file transfers, but those read speeds are way too slow to deliver any performance benefit to a Windows Vista PC. It fails.

This 1GB drive from A-Data, purchased from an online outlet store, just failed to clear the minimum required write speed on the first test pass.

After retesting the previous drive, write performance cleared the minimum threshold, but this drive couldn't deliver that speed across the entire drive. Its design uses a single fast 128MB flash chip matched with slower flash chips. Because it couldn't deliver consistent results, ReadyBoost refuses to use it.

This older drive, a 256MB PNY Attache, was surprisingly fast, delivering scores roughly twice those of the ReadyBoost minimum spec.

Apacer's Handy Steno 2.0 USB flash drive (1GB, in this case) delivers the fastest ReadyBoost performance scores I've seen. These numbers are roughly twice the performance of the next fastest drive.