The Celeron 900 on a 112MHz fsb for 1008 is still gonna beat the 600 P3 on a 133fsb. Sounds like you are almost stable at 1200MHz, even though you are not real hot, a better cooler could still make a difference and give you 100% stability. I know it's kinda late now, but the 800 Celeron would have been a better choice, it seems to make the 133MHz fsb every time.