CPU mining is bad; they're not that well suited for hashing as GPUs, their cost is too much in comparison to their hashing speeds and you can't scale them (1 PC = 1 CPU, maybe 2).
using a gui miner i can use 4 cpu's and have had success mining many altcoins, we are on solar power here and I'm curious to know if the high power bills were the only reason people say cpu mining is dead? I've got my eye on a new desktop computer with octo-core processor for my next mining project.