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My former place of employment sold both 1 GHz p3's and 1 GHz Athlons on a 145 watt PSU. Those PSU's are only rated for 8A on the 3.3V rail. The 1 GHz P3's usually lasted fine, the Athlons tended to blow up (the PSU). I GHz athlon should be fine despite what most ppl will tell you. Doubt it will win stability awards, but it will work.