I have tweaked my Asus RX580 (8GB) according to best guide and not getting over 1000 hash on each.
I dont think its possible unless you having clocked it to have hundreds of memory errors and card then fuck up..
So! If you don't know how to do it then it is impossible?
Didnt say its impossible, just saying with the dodgy overlocks your not considering power draw.
Considering the safety of your cards, then good luck with your power bill vs profit of mining.
Good luck with the life of your cards..
You need good timing straps to reach 1k+ on CN-V7. 8gb cards can do 1k+ on CN-Heavy easily.
I have also got 1260 H/s on an RX 570 8gb card (1466/2300 clocks). They do 1140 H/s @ 1250/2240 clocks and 900mV core (105w from wall). So it's pretty much possible.
Also, All 4gb cards that I have Elpida, Hynix do 1k+ on CN-V7.
I want to see that...
Can't get more that 700h/s with Elpida 570 pulse 4gb (with stak and SRB)