a-4) Test In case the pins of the very first chip are certainly not soldered properly (it was present in repair that the pins are tinned observing in the side, though the pins usually are not stained with tin in the least in the event the chip is removed) https://antminers19prohashboard32086.bloggosite.com/38165490/the-2-minute-rule-for-antminer-s19-hashboard-repair