Ive had a few and they didnt seem very effective to me. The ammount of air they pushed was low, and it seemed that they recycled the warm air from the GPU more than anything. All in all the ones i have had were a waste of money to me. If your case supports it [or if you know how to dremel] I would install a fan into the side of your case parallel to your video card. That will knock the temps down drastically [15-20c at best].