I have 3 Vega 56 cards. One MSI and two Sapphire reference cards. I was running them in my gaming PC and everything was working ok. Had two attached to the Motherboard and one on a riser out of the tower, with the side open. They were running fine. Hashing 5700 H/s on Cryptonight with no issues of instability.
I built a rig for these cards so I could get my gaming PC back and have had crazy instability. I am not sure if it has to do with the PCie SSD that I am using in the M2 slot, or that I am using 3 risers now but it keeps crashing. Anyone have any experience with instability and no real solutions to be found? I feel like I have tried everything. I have use Wattman, use OverdriveNtool without wattman but nothing seems to be stable. I just removed that SSD and installed a new version of Windows on a Samsung EVO SSD. Hopefully this works. (Will update later) Maybe windows install was corrupted on the other hard drive. Also, I do not think it has to do with temps, since I have a giant box fan blowing on the cards and have the fans at 3000 or max at times.
Hardware below:
Z170-AR motherboard
https://www.asus.com/us/Motherboards/Z170-AR/
Corsair AW1200i Power Supply
http://www.corsair.com/en-us/ax1200i-digital-atx-power-supply-1200-watt-80-plus-platinum-certified-fully-modular-psu
8 GB of Ram
A PCie wireless card
Risers
HDMI dongle
I have been using Hella's guide on Reddit and Circusdad's guide but nothing is working. I went back to original BIOS, ran DDU a million times it seems but I keep having issues. (Also done the disable driver thing, and using Teamviewer) Do I need to change the PCie lane settings to Gen 1 or Gen 2? Any ideas are appreciated. Any opinions on what it could be? The miner runs for a while an then crashes randomly. Then I see no hashes to the pool and lose my mind. Please help me get my sanity back.
Btw these above guides are great. Please feel free to share your own experiences and maybe we can help each other.
Update, 28-Dec-17: Make sure you do not use the CPU to mine in the dual miner. I have heard from a few Vega builders that this caused many issues. Unless you have a powerful CPU don't bother, the extra hash from mining with the CPU will just take away from GPU mining.
I replaced the risers, with the below and it is all good now.
https://www.amazon.com/gp/product/B074Z754LT/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1