From my experience (Includes a K6-2 on ALi Aladdin V, Celeron on SiS 630S, Duron on VIA KM133, and Celeron 533 on Intel 810), they're all stable, with the exception of ALaddin V, I had nothing but trouble on it, but the other 3 are identical in stability (notice nbo difference between SiS and Intel chipset).