a semprom is a single core, low power consumption, low cache and also low performance solution, it is the smallest option from amd designed to cover the minimum requirements
depending on what 3200 you have, single core possibly, a big semprom can match it or be close to it, a 3200 runs at 2.2 ghz and recent semproms run at that same speed but using ddr2 or ddr3
a phenom II is at minimum two cores cpu(i wouldn't buy a two cores, 3 or 4 minimum)latest and greatest cpu from amd
it is fast(each core at 2.7 ghz or more, lots of cache, upgradeable(shares am+ socket with many other amd models) between many other good things it offers
between a semprom and a phenom there is no comparison, a phenom offers at least triple of the performance of any semprom existent