Re: HD 5770 Directx 11
I'm afraid Direct X 10-11 is indeed Vista and above only. XP doesn't support them (though whether that was a tactic by Microsoft or not to get people to upgrade, I don't know)
Direct X 9 should work though, as long as you have the correct ATI drivers from their site installed, and aren't running off a default set of drivers included with Windows.
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