1 Go for rx 470 s if you know how to over clock and bios flash . If you go for 470 s go for the sapphire rx 470 nitro 4 gb you do not need 8 gb if you know how to bios flash and overclock you would just be wasting money . 2 for the motherboard I have the msi gaming 5 has room for 7 GPUs and I use powered risers newegg at least in Canada has a great deal on this one right now 3 if you follow my advice and go with the rx 470 s and do some undervolting and overclocking 750 watt will be good and you can always do a dual psu set up if you end up getting more GPUs . 4 just get a cheap ssd they are so cheap these days and you don ' t need lots of storage so why not . 4 gb is fine . Cheap cpu is fine but in my case it has caused my rig to crash while trying to set stuff up just cause it couldn ' t handle the amount of tasks I was giving it . Trust me this is the most cost efficient way to do this . If you know what you ' re doing of course . If you don ' t feel comfortable with changing your bios and overclocking just go for the 480 but my 470 s get around 30 . 5 mhs and I use under 100 watt .