External HD Not Detected

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I've had a 200 gig external for some time now. It's always worked fine with Vista. All of a sudden, Vista no longer detects it. It does not show up in my computer nor does it show in disk management. Restarting obviously did nothing. When I turn it on, I heard a noise similar to the "new hardware detected" noise that Vista plays except this one sounds like its powering down.

I confirmed my HD works by plugging it into my roommate's computer where it works fine. The USB port definitely works.

It is a Lacie Brick hard drive, 200gig model as stated before.

Any ideas?