I bought an HP Elite i7 system last year. I have been pretty happy with it overall. At Christmas I installed an MSI GTX460 with the Cyclone cooler. The cooler exhausts internally and the card runs at about 75-80C under load at stock clocks. I can feel a stripe of heat along the side of the case where the card sits. If I remove the side of the case the card runs at about 65C.
Yes, the interior is pretty cluttered. I cleaned mine up by pushing all of the wiring above the HDD cage and zip tying it together when I installed the video card. Also notice that the CPU cooler doesn't have a fan of its own. There's a perforated area on the case side directly above the CPU cooler. It looks to me like it would let cooling air bypass the CPU cooler somewhat. The CPU never gets above 65C though.
I had a couple ideas to try and get better cooling to the GPU.
1. Block off the vent over the CPU so the case breathes from the front vents.
2. Cut out the grill over the case fan.
3a. Wall off the airflow from the front half of the case over the CPU cooler so it has to pass by the GPU before it hits the CPU cooler.
3b. Make a duct on the case fan so that 1/2 of the air is pulled through the CPU cooler and the other half is pulled from the area below the GPU.
I got a couple suggestions off of Anandtech. One was to add a fan above the HD blowing towards the GPU. Another suggested cutting the side of the case above the GPU.
Here are a couple pictures of the case I stole from the manual:
Idea 3A Block added in Yellow
Idea 3B Duct added in Yellow
I'd appreciate any input you guys could give me.