Hello guys

I build 2 Rigs
1)
Asus b250 mining expert
8 x sapphire rx 580 8gb nitro+
Corsair tx750w x 2
120gb ssd
Windows 10 64
16gb ram
I3 7100

2)
Asus z270-p  
6 xfx gts xxx rx 580 8gb oc
Raidmax cobra 1200w gold +
120gb ssd
Windows 10 64
4gb ram
Dual core processor

Both cards are giving only 18mh/s and temperature is between 72 to 77 for all cards hashrate out of the box & i don't know y. And the 1st rig displays every few minutes errors in miner & keeps on disconnecting from internet, plus it stops mining if you stop using keyboard or mouse