RX 580 Low Hashrate - 11-12 Mh/s

To start, I'm new to mining. Put the rig below together in Dec '17 and after reading a thousand forums here and reloading everything 10 times over several weeks I have a stable rig.

I have been mining XMR with this setup on Minergate for a few weeks fairly stable. Cards are averaging 600 h/s (3.6 k/h total for 6 cards). This sounds on par with what I read for stock bios cards mining these algorithms. I decided to see what the cards would do mining ETH and I'm only getting ~11 - 12 mh/s per card (~70 mh/s for 6 cards). I see a couple mentions of this issue on forums but haven't run into anyone who has solved it. Any Ideas!?!? Thanks!!

Update: Same rig runs ~25 mh/S on claymore. Minergate seems to show exactly half the hashrate on their dashboard. Funny thing is I feel like I accumulate Eth faster on Minergate despite the hashrate shown...

MSI Z270 SLI Plus (4g / gen 2)
8GB Ram
64G SSD
Cely i3 3900
3x Sapphire Pulse 580 8g (No Mods)
3x XFS 580 8G (No Mods)
2x 750w PSU (3 cards / 3 cards + Mobo)
Windows 10 Home (UEFI)
AMD Crimson Beta Driver (No Compute Setting Available)