I am looking to set up a dedicated rig to mine ETH or XMR. I only has a HD7950 from my scrypt mining days. Which GPU has the best power efficiency at the moment? This is my main consideration since electricity is not that cheap in my city (about $0.15/kWh).
Would go for the RX 480 cards , with some simple bios mods , or wattman tweaks you can get the power usage down , hash rate up .
My bios modded rx 480 8GB cards are hashing in the 30MH/s range (ETH mining) GPUZ reported wattage between 65-85 watts , real wattage at the wall is around 115-125 watts /cards .
You can get RX 480 250$ - 300$ , nvida 1070 from 400$ and up .
My 6 cards setups is pulling around 880 watts at the wall with modded bios with a total hashing power 178-182.5MH/s , the same setup with factory bios , way under clocked pulling around 725 watts with a total hashing power 148MH/s . Without any modification , tweaks ,with stock bios , the same setup is using 1100watts at the wall with 148MH/s hashing power .