How'd you connect a fan controller to it? Did you modify it?
Anyway, there's no way that I know of right off to check the heat of your PSU. I'm sure if you had one of those little thermal sensors you could stick it in there. Not that I'd know the best place to stick it, or would I reccomend doing that...
Most PSU's don't have any issues as long as their fans are running normally. I know mine has a built in controller and actually tends to run rather hot(as in just feeling the heat out the back) However, this seems pretty normal amoung higher performace power supplies.