best gpu for gaming and litecoin mining

[Torrid Rattlesnake]

hello guys,how are u?i started this topic because i want to get a new powerful gpu so as to play games and do some litecoin mining.my budget as for now is 750 euros.i was thinking about taking to sapphire 290s but i think that 780ti is perfect for gaming but its awful for mining.my first priority is gaming,but i would also like to have a good gaming machine that can mine litecoins quite fast.thats why i think that the 2 290s are better in this but i would like to tell me your opinions guys
P.S shall i buy any antiminer usb to mine bitcoins?
P.S 2 there will be any usb erupters for litecoin minig and if yes when will they be available?
P.S 3 if i buy these cards now,will they be compatible with pcie 4.0 with skylake(i intend to to buy new parts in 2 years sooooo.
OR should i just stay with my 7870 i my 1680 x 1200 monitor and upgrade everything including gpus in 2-3 years?????

 

[Torrid Rattlesnake]

and if i get a cheap full hd monitor the 290s or 780ti will be futureproof.thanks in advance