M17x 6990m / 6970m overheating

How to fix AMD 6900 series cards overheating in the Alienware M17x.

I have been having overheating issues with the 6990m crossfire setup in my M17x R2 for a while. It took forever to finish Deus Ex because of random crashing, and now I’m playing Bioshock and having similar issues. I already undervolted the card which helped but wasn’t enough. What I figured out was the GPU heatsink / fan design is a bit flawed. The heatsink isn’t close enough to the back of the laptop where the exhaust ports are, so the positive pressure created by the fan can’t force the hot air out through the honeycomb grill material. To make matters worse there is a horizontal bar directly in front of where the air would escape. The hot air is then mostly recirculating inside the computer instead of being pushed out by the fan. Take a look at the CPU heatsink / fan design to see what I mean, it was designed correctly.

Instead of trying to create a duct that would connect the heatsink to the back exhaust ports I decided to just give the laptop a proper exhaust port. I removed the honeycomb grill and cut out the center bar, as well as removed a bit of material on the inside of each port that was blocking flow completely. I made sure not to remove anything that wouldn’t be covered by the honeycomb grill, but I decided not to put it back in anyway as all it’s going to do is impede airflow. The effect is very noticeable: where I used to be able to put my hand on the rear ports and feel little airflow but lots of heat in the chassis I now feel just a blast of hot air. I haven’t had a chance to test extensively but already I have much lower GPU temps and Bioshock hasn’t crashed yet.