Again, power is not an issue.... you've simply picked a poorly designed case for such a system. In the end, if you want that case no matter what, just go with it... how bad can it be? 
If you set up the radiator's fan as an intake, you'll be dumping all the heat inside the case, essentially sabotaging yourself.... if you're setting it up as an exhaust you'll be fighting convection (not desirable but it's not gonna' kill your setup either).... not much else you can do with that case.
If you set up the radiator's fan as an intake, you'll be dumping all the heat inside the case, essentially sabotaging yourself.... if you're setting it up as an exhaust you'll be fighting convection (not desirable but it's not gonna' kill your setup either).... not much else you can do with that case.
