Instable Rigs with Saphire RX480 8GB Nitro OC Cards

[jadefalke]

Hey Guys,

i have multiple Rigs with the following Configuration:

ASROCK Pro BTC Mainboard
6X USB Riser
6X RX 480 Nitro OC 8GB
Celeron G1840+4GB Crucial DDR3 RAM
Seasonic 1200 Watt Platin PSU

The Rig is build pretty strait forward and running with Ethos, it is starting quite ok, but then after a time cards start to stop hashing.
Some rig's do better and only one card is failing other have 3-4 Cards failing. I tried also another Mainboard (Asrock Anni H97)
but the Problem is still the same.

I think it has something to do with Power distribution or the Cabeling. The PSU has 7 Dedicated PCI-e Connector so each card has an own 8 Pin Connector, the Riser are powered via SATA Cable, 2 cards share one cable from the PSU. On one Cable the SSD is also connected.
I tried to move cards around on the PCI-E Slots but that does not changed the Problem.

Did anyone encountered same Problems and found a Solution?
Any Help appreciated.

[bobben2]

It could be power related.
Did you try removing a gpu to see if it became stable?

[dakky]

I had the same problem with Ethos and XFX RX480 8GB... tried everything, from disconnecting one or two cards to auto-restarting the rigs when the cards fail... eventually switched back to Windows as there was no solution within Ethos.

[jadefalke]

I had the same problem with Ethos and XFX RX480 8GB... tried everything, from disconnecting one or two cards to auto-restarting the rigs when the cards fail... eventually switched back to Windows as there was no solution within Ethos.

interesting, but windows is not really a solution for me. Thanks for your input.

[jadefalke]

It could be power related.
Did you try removing a gpu to see if it became stable?

that will be my next step.