I just bought an AMD sempron 2900+ and I was under the impression it was going to come with a heatsink but it didnt so I was wondering will I be able to use my athlon XP 1200's heatsink instead? Or will the processor overheat? I tried going to compusa but all I could find was heatsinks with fans for 1.2ghz and up...I didn't know the heatsinks were classified by the speed of the processor.