Running Rx570 and 580, only two cards so far on this rig. Getting 24Mh/s on the pcie 1x slots, same card same riser plugged into the pcie16x hash rate drops down to below 12Mh/s. Tried the card in different slots, same results fast in pcie1x, and slow when connected to pcie16x
Tried on both Pimp and ethOS, replaced risers, swapped power cables, same result.
Try plugging the card directly into the 16x without a riser, since you're not using anywhere near all of the slots anyway?
I haven't tried booting the board with no card in the 16x, that might also be an option to just ignore that slot.
I'll try that thanks
I ignored Pcie 16x too, only worked with pcie 1x with 13 cards, and all works perfect.
How many PSU do you use?
I use 1 EVGA 1300W and 1 paraller miner PSU 2400W