Re: Ethereum mining still profitable?

My unvoltaged and underclocked 7970 uses about 140W to have 20MH/s. So that is less efficient than the 970.

I think it is similar efficiency. the difference is very small. 7970 is 3-4 year's old card.

7970 20MH/140 = 0.142.
970: 20.75/147 = 0.141.