One thing I've noticed when talking to novice computer enthusiasts are that they often use too many case fans in an attempt to keep case temperatures down. While their hearts are in the right place, most run into the common problem of having too much 'positive air pressure.'
What I mean is, if there are more fans blowing air into a case than exhausting from it the air pressure just builds up. What we need is the airflow entering into the case to be matched by the air exhausting from the case so air currents don't stall.
If the air has no where to exit, it can't very well cool your $500 videocard any better now can it? What I recommend is that enthusiasts focus on creating a situation where your case has negative air pressure (more exhaust fans than intake fans simply) inside a case.
This has the tendency to pull fresh cool air into the case, and ensure some guaranteed air flow in and around the exhaust fans. In most cases, a system with negative air pressure should run cooler than one with positive.