I think AMD cards would be the best choice since the price of AMD cards is more cheaper than nvidia card if you build a 6 ot 7 gpu go to for AMD cards i think you can buy 6 or 7 GPU including mobo, riser, ram and ssd. .
Possible you can earn of almost $15 to $30 from recent price and difficulty and depends if what GPU you choose..
Thanks, i know AMD and Nvidia this two companies GPUs are better than others but they are not available for ship in my town. I have to visit the second place to buy it then it is better to buy gigabyte this company has also good reputation. Has?
I will post images and links with my all accessories.