Hey, I'm new here and I see you have some cool and helpful people around.

So here's my thing, I'm will be building a GPU mining rig as efficient as possible, and I'd like to have 7 GPU ( I already own 2x Sapphire 480 4gb and 1x with 8GB, 3 in total), 24/7 and last as long as possible, years even.

Here are my questions:

1. Z87 Mpower Max - It has 7 necessary slots and I heard people make it work, but I keep hearing about "shorting the pings on the PCI-E for motherboard to recognize all 7 GPU" I don't know what this means or how to do it, if it's dangerous or not, is there anyone who can help on this. The Reason I like this MB is because I can get it cheap, and I can get 1150 CPU and Ram for it for free , also it has Wi-fi integrated so I can put it in the basement without cables.

Same question for Z97-G45!

Now if you don't recommend the MB above I could look into the Z170 msi Carbon +cpu+ram and try to squeeze some extra cash .... eventually adding a wi-fi usb adapter.

2. PSU- they are not cheap where I come from, and I will be running the rig 24//7 for as many months as I can. Should I get 2x PSU 800w gold with warranty or brand new 1600W gold without warranty from a seller for the same price. Also if I were to get two of them, what adapters should I use and could there be any other problems.  1200W GPU and above are super overpriced, but if necessary I'll look into it.

3. I'd like to keep the GPU's at lowest temps possible, so I'll most likely underclock a little, while getting the best out of it, so what GPU's would you recommend, and could you point me out to tutorials on how to flash their bios so I would get the best hashrate for low temps.

Any other advice would be welcomed because I have worked really hard to raise some cash for the rigs so I wouldn't want to blow it.

Thanks in advance!