If its blowing directly at the NB it works every well. I know cuz i tried it but not stuck on the side. I put a 80mm fan sitting on the back of my video card which faces directly at the NB when the case is sitting up. That was my solution till i got the 40mm fan. It work better actually, with the 80mm in the NB's face the NB heatskin was actually COLD. The reason I stopped because I put a VF900 on the card so I cant put a fan on the back anymore and I didnt feel right with a loose fan in my case. 8O