R390 eats 200W with 270 sols
R7970 eats 165W with 184 sols
R7950 eats 110W with 170 sols
Every card is undervolted.
Most efficient is 7950 1.54H/W.
R7950 eats 110W with 170 sols <-- That is more efficient than the 400 series...
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Sapphire nitro+ rx470 8gb Samsung :
70W -> 160H/s = 2.28H/W
What the application is telling you isn't accurate. Please provide measurements at the wall.
r9 nano 235 hs , 80 watt from wall (880mv , 800 core, 350 memory)
best buck is TAHITI
best buck for future is RX
the most efficient is NANO
sory guys TRUE KING IS NANO
on ETH tahiti have same watt with RX in heavy undervolted