6 gpu rig not working

[l;egomanjoshm]

hi I have a mining rig that I have all the cards registered on the device manager but when I go to mine with claymore dual miner one card is unable to load the dag but the card works perfectly when I put it in another computer to mine so I'm wondering if theirs a bottle neck I'm missing on something.

rx 480 8gb nitros modded

biostar hi-fi h81s2 mobo

8gb ram

windows 10