I'm new here but post a bit on anandtech. I experimented with passively cooling a low profile HD 5750 in an NSK1480. This required bending the heatsink significantly, but with a bit of effort, it fits, although it is now a quad-slot video card. Generally it works well. I'm having some issues with blue screens which I think are caused by overheating (in a dual display config with the Intel HD 2000 IGP, only the Radeon display shuts off while the IGP display displays whatever was showing before, and then the computer resets after another 10-15 seconds).
The weird part is that the AMD utility is showing very acceptable GPU temps of around 75-80C at load; with the stock cooler I was hitting 95C without crashing. Also, the two exhaust fans (Noctua + S-flex in pics, 2 Noctuas now) make a difference. If I run them at 900rpm and stock GPU, I get no crashes. Overclocked, I need to run at 1300rpm to not crash. Either way, the GPU temp readings are good so I'm thinking it's either the memory or voltage control.
Any suggestions which? Am I being greedy?