With abit you get uGuru, which is very nice for overclocking.
All you do is go into uGuru in the bios and set you external clock to 220Mhz to get 2.420Ghz. After that requires you to know a little about overclocking, which I don't know..
You might want to run the cpu for a few days at the stock setting first though to break it in. Mine was very picky about overclocking the first day, after a few days though 2.4Ghz was as easy as changing the external clock from 200 to 220Mhz
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