every psu has at least one 12volt rail. it is absolutely neccissary or else ur pc would not function. it provides power to most of the copmnents. some psus have a higher rated single rail and some have multiple sligh;ly lower rated 12v rails. i recommend you get a 450watt corsair or antec psu. also seasonic is a good brand.
cm is not known for its amazing psus, they are moderately ok, thouhg, as long as they arent stressed to much for too long.