2 cheap solution's
1. Like you said run a fan over it.. make shure its !!good!! quality otherwise you will get a little bit of a wave motion beacause the motor produces elctromagnetic wave's. it wont harm your card its sheilded however it will mess with some otehr stuff
2. run with side pannel off and prop a 88/120mm fan blowing air away from it on top of it just lay the fan down on top of it make shure you fan fins arnet hitting the factory fan mounting screws.