On Sat, 4 Apr 2009 05:22:18 -0700 (PDT), Big Jim
wrote:

Passive venting does nothing. The regular fan with a thermostat will
be far better



I don't know where you got that notion, but it's wrong. If you have
soffit vents and a ridge vent done properly, it will be far more
effective than any fan you install. It's not even close.