just before you buy check what kind of slot it uses. If it's really really old it'll be a PCI one, if it's not so old, it'll be an AGP one, and if it's new, it'll be a PCI-E.
I know, kind of confusing 
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One of God's own prototypes. Some kind of high powered mutant never even considered for mass production. Too weird to live, and too rare to die.