the k6-III is practicaly just a revision to the k6-2 cpus,same weak fpu etc,however the k6-3+ has extended 3dnow and lower voltage and overclocks up to i think 840Mhz(140fsbx6=840).it also spanks even a pentuim 1000Mhz at interger stuf. also their is one big difference,price and qunity.