You may also download the bios update file from another computer to a usb and then update your bios using that usb. Update procedure changes depending on your motherboard so googleing it or looking at the manual may help with that.
I would recommend checking all the connections, specially the cable that goes top left of the motherboard from the psu (it is the one that brings power to cpu).
I am plannin to reset my wimndows 10 pc and clean everything on it. Any idea how long it would take. Intel core i7 6700k, gtx970, 16gb, 256gb samsung ssd, 2tb westerndigital black hdd.