NiceHash - RX580 and GTX 1060 won't mine at the same time

[Dzhimen]

Hello guys.

 

I built a small hobby mining rig (nothing serious, mostly from the parts I had on hand) and I'm having a strange issue with the 2 GPUs I'm using and I was hoping that someone would be able to tell me what's the source of the problem I'm experiencing.

 

The build is:

- Gigabyte GA-H110M-S2H

- i3-6100

- 2x4GB DDR3-1600 RAM

- XFX 550W 80+ Bronze PSU

- KFA2 GTX 1060 3GB

- PowerColor RedDevil RX580 8GB

 

Now I know the parts kinda don't make sense for mining, but that's what I had from before and I'm not currently interested in investing into a new motherboard, for example, with the current state of things regarding mining... So I'm specifically looking for the source of the issue. The system is running on a SSD with Windows 10 and the latest NVidia and AMD drivers installed.

 

So the motherboard has one PCIe 3.0 x16 slot and two PCIe x1 slots. I put the RX580 directly into the x16 slot, and GTX 1060 on a riser (x1-->x16) on the bottom x1 slot (the other x1 slot was being covered by the RX580 fan cooler. RX580 requires a 8pin+6pin, the 1060 requires a 6pin. Bacause the PSU only has one PCIe power cable, I plugged that into the RX580, and for the 1060, I used the adapter (2xmolex-->PCIe 6pin) that came with the KFA2 1060. From all the online calculators I found, the 550W should be fine for those two GPU-s at stock speeds (again, I would buy bigger, but that's what I had at home), but just in case, I tried supplying the 1060 with 6pin PCIe power kable from a secondary PSU (Seasonic 360W 80+ Gold), and the problem was the same, so I think I can eliminate the PSU as the source of the problem. 

 

Both cards get detected just fine, and are working. When I open NiceHash miner and mine with only the RX580 (plugged directly into x16 slot), it mines fine, load goes to 100%, no problem there. When I mine only with the 1060 on a riser, it also Works fine, load to 100%. But when I try to mine with both of them at the same time, either none of them work (load goes up for 2sec, then back to idle, then after 5s idle, the load goes back up, but only for one or two secs, then back to idle etc. and NiceHash, displays 0 $/day and 0 MH/s), or one card mines fine, as it does when I mine only with that card, but the other one doesnt work (as previously described). I can't get them to mine at the same time. 

 

I tried swapping them (1060 directly onto x16 slot and 580 on a riser into x1 slot), no difference. Separately they worked fine, but together, they didn't. I tried supplying the 1060 with a secondary PSU wihtout the adapter, so directly from PCIe cable, still no difference. I tried two NiceHash instances, made no difference. I am currently mining with the 580 in that system and the 1060 in my personal PC, and they both work fine, runnung for 3 days now, no problem. But I would like to run them both on one system.

 

Would anyone happen to know any apparent reason why this is happening? A Google search revealed that some people have no problem mining with both AMD and NVidia in NiceHash at the same time. Is it the problem with the PCIe slots on my motherboard? Maybe problem with the riser? Or is it a NiceHash problem?

 

Any help would be greatly appreciated.

 

Thanks in advance!