No reason it shouldn;t work, but good airflow in your case is probably easier and would yield the same results, if not better as the airflow would also cool the other components on the video card.
Thanks to BradleyKZN for polishing my sig
“oooooooooooh fire!!! and girls...GIRLS and fire!!!!!!! oooooooooooooh *runz around clapping hands together*” -Marineborn