This is 6u I have yet to be able to get 2 PS, mb, and 6 gpu into less then 5 and even then there is very little room for the top connectors on the gpu's

PM me for a phone number to chat if your interested.

below is a link to my shop

http://www.mtekcorp.com/company/images/lg/pano2.png

I can do it in 4u if you don't mind it almost 30" deep.