I have 2 rig's mining ETN at the moment with a total of 7 cards. All my cards seem to work fine as far as i can tell. I have never heard of any limitation for how many cards you can mine a coin with. There are thousands of GPU's mining across the Electroneum network so weather you have 1 or 50 GPU's they should mine fine working together. What OS are you using ??
I find that ATI's work best on Windows 10 with the blockchain drivers, And for Nvidia's i use Windows 7.
My main ATI rig has three RX560's mining at about 360h/s each.
One RX480 @ 800h/s
One R9 290 @ 880h/s
On my second rig iv got 2 older Nvidia cards
One GTX580 @ 380h/s <--- Fast for a old card lol
One GTX780 @ 290h/s
I also have my main PC With 8 core Xeon's doing CPU mining for ETN running at about 200h/s
Dont know if this will help you at all. But id be interested to know what GPU's your using and what speed you get?
Hi,
what are Your R9 290 settings? Mine hash around 720 H/s.
Custom or original BIOS?