I use powered PCIE risers in open case, I put extra fans to extract heat out.
The original thermal past is extremely thick. I tried to apply thin layer of thermal paste, the improvement is minimal, just 2-5 degree, as the heat sink cannot touch the GPU evenly, even after I adjusted the force with the 4 screws. That could be the reason why manufacturer apply a thick layer of thermal paste.
Thanks for your reply, I very much appreciate it. You've got a lot of hashpower there! Probably about 20Mh/s - I'm just bumbling around at 3.5MH/s.
I might look into reapplying the thermal paste when I have time and the coin craze calms down a bit. Even 2-5 degrees are worth it, particularly if I get 5 degrees less on the hottest GPU. I've also tested the limits a bit on my cards - one card is great and seems to go up to 1000/1000 on 1.02V, but the other cannot cope as well and crashes above 960/1000. I do like to keep my cards cool <72C, so I'm sticking with lower settings. It's all great fun.