3gb is fine for all games out atm. especially d3. it's got a higher ram speed with the new pascal architecture
it's maybe %10 slower than 6gb but yeah.
also it's less power hungry and less heat.
up to you tho
(either cards would be fine.. in my opinion it's 1060 3gb > 580 4gb > 480. but in real performance it's 580 4gb > 1060 3gb > 480. their all very equal though biggest jump is 480 to 580
but re-thinking if you get a 8 gb 580 then do that all the way.. but it's just like getting a 6 gb 1060..
This post was edited by Jarester on Apr 12 2018 02:16pm