they don't have a psu, they buy in bulk what they need

calculating an 4th miner put in function 2 months ago is ~600$

why do an 3th miner when overclocked s4 is up to 2.4th and 2 s5 is like 2.8th

why do an 3th miner when spondoolies had an 5.5th miner in same format

also 2*s2=s4, so 2*s4=....