I'd like some Thermal Dynamics Advice for my rack.

I have a couple of choices, I need to decide on some combination of the folowing:

Pull air from underneath the house, always in the mid 60's (but is moisture a problem?)

Pull air from the conditioned space

Vent to the attic using induction

Vent to the attic using a $450 remote attic fan with a heat rise thermostat controlling the attic fan.

Considerations:

I can seal the rack to a point, but there will always be leaks between the gear pulling from the conditioned air, just not adding vents)

I'm in North Carolina in the foothills so 7/9 months of the year is probably not to much of a problem, the other 3 months.. NEED temp control.

It's a 45 space rack (almost floor to ceiling)

Included in the rack right now:

Onkyo M-282 AMP
Sherwood Steroe Receiver
Onkyo 706 Receiver (probably a Onyo 9.2 or Denon soon)
Server 8 bay hot swap
Server expansion Case 10 bay hot swap
HTPC Media Room (maybe one more HTPC)
Xbox 360 (future 2 more)
One Cable STB (may go away)
UPS (for computers)
AVR (future)
24 port GB switch
Media charging station (cameras/Headphones/Etc)
Squeezebox Controller
External Networked TV tuners
Moden/Wireless Hub

LOTS OF HEAT GENERATING!


Right now it's about 76 degrees outside and the Rack Temp Gauge is at 91 degrees. But it's open to the garage (unopened) and the master closet (AC registers closed). Actually the rack isn't closed in in any manner yet. But where the temp gauge reader is is at the top with no where for the air to go, the rack isn't really that hot.

Any thoughts appreciated!
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Fronts/Wides:M22s in/on
Center:VP150/VP100 in/on
Hghts,SS,SR:QS8s
Sub:EP500
AVR:Onkyo 3008