What are the best GPUs for mining altcoins? isn't it odd that there are GPUs priced at $1000 and even more but when you benchmark them you'll see that for mining they are not worth a penny 
for now the best seems the 470 on zcash with its 120 sol, otherwise for nvidia you only have the 1060 3gb which cost a bit more and does only 65 sol or something
but consumption is lower for nvidia, because of no proper optimization also, anyway i would probably not buying a new rig now
How are you getting 120 on your 470? What mem straps/bios?
i don't have a 470 rig, but you can do 120 sol by using optiminer or whatver is called, it's another miner more optimized, check the thread on the zcash forum