well the 10 inch will use 80 watts which means a splice into a molex and the molex allows 3 power choices been a while since I did that but I think the correct wiring to a molex will yield 9 volts which should still let that fan pull tons of air.
I think I will take this one on and try to build one. I have cards I have mobos I have the case. so why not
Thanks for the update philip, about the setup. here is what I was thinking, which in my opinion will make enable efficient airflow.
http://i838.photobucket.com/albums/zz305/BLife12/2%20PSU%20Controller/Setup_zpsmc7xlc8f.pngHere the fan is mounted to the top with the case having a vertical limit of about 9". And the GPU's are mounted at an angle of about 70 degree that makes them blocking the channel and any air flow has to wash over then, that will in my opinion will help in reducing the heat a lot. Each channel can be about 12CM wide which will give ample space to mount the gpu at that angle.
So the breth of the case will be about 6*12 + 5CM margin = 77cm. This is a big but I hope this will help.
Any ideas and criticism is welcomed. If anyone else have any ides a please post them here.
Regards,
BLife