Actually the current street value of an Athlon 550 is only about $250USD where as the PIII 550E is marked at $350USD. That when looking at comparitable clock speed pricing. But also note, the comparison on sharkey was to an Athlon 600, and even this case Athlon 600's are running at about $375USD street price. So, you're only paying ABOUT $5USD more for that 10-15% speed increase... as well as getting a better chip and (as stated earlier by others) "overclockability" to upwards of 800 with an Athlon 600... sounds rather worth it to me ;^)