I own a 4600Ti PNY card, and it is prety good. I had to RMA it recently (they sent me a bad card), but all in all it was a prety good overclocker. I got it to just over 12000 3dmarks without even trying, and stock cooling.
google is your friend
http://www.gamingillustrated.com/xfx4600.php
Doesn't look like a good overclocker, though...
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Yo-DUH_87
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