2x Biostar motherboards fail

I bought a Biostar Pro 12 GPU motherboard from Wootware to build a test cryptocurrency mining rig. I bought 8GB Ram, i3 Processor, and an 850 Watt power supply. I used my Corsair 550 Watt power supply first to set up the board, with a few intermittent startup issues, I managed to get the motherboard up and running with one card. I added another card and the system didn't want to start, so I finally moved to my 850 Watt power supply and with tampering on startup issues it blew the motherboard, I sent the board back and during shipping the CPU protector apparently came loose and damaged the CPU socket, I have pictures of a pristine socket before sending the board back. I then purchased another Biostar board and CPU chip and am still experiencing intermittent power on issues even with a 1600 watt power supply all I've plugged in is all the motherboard connectors and a hard drive, the fan spins for 4 seconds and stops "No Power". Biostar and Wootware passed the buck and no one has replaced the first board and processor, I must add that the 850 Watt power supply also stopped working but on inspection from the power supply supplier the fuse didn't blow.