you can lower heat much more by adjusting your PSU to lower voltage. For example Fortrons have adjustable potentiometer accessible through fan hole without removing any screw. You can adjust down to 10.8V which reduces heat of S5 a lot.
link to one please. thanks
I am currently using Fortron Raider series or low cost "raiders":
I tried to find official link, I have black one, but should be the same:
http://www.fsp-group.com.tw/index.php?do=proinfo&id=1667I killed a lot of them during GPU times and found that there is no difference in power output between 600 and 750W.
Voltage mod can be done almost on every more powerfull PSU, like Fortron EPSILON series, or a ton of other brands, but older PSU dislike rising voltage due to 5V and 3V3 rail OVP.