I'd say overclock it. I don't like flashing, i always think something's gonna go wrong. It's just as good that you get a program like ATITool or ATi Tray Tools to reset the clock on startup. Both are good. They both do pretty much the same thing. It's just that tray tools is limited to just the toolbar. Also, the tray tools one is newer, and has support for per-game profiles, which means you can make it overclock your card only for certain games you run, when you run them. And you can set AA and AF from the tray too!
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