It's recommended.... Depends on which Athlon... the XP type are way more finicky, not to mention power hungry. My fried ran a 1100ghz with a 250 watt power supply, and then upgraded to a 350 watt as his XP proc would not work right and locked up if you did anything intensive at all... I warned him... IMHO, spend the extra $10 and get a decent PSU. -TAL
And then again, for lower end Athlons.... Like my 750 SLot proc, I use a real crappy PSU....