I've been having a problem with my mining rig over the last week. My rig consists of the following five GPUs: (2) GTX 1070s, (2) GTX 1060s (6Gb), and (1) GTX 970. My motherboard is an ASRock H81 Pro BTC R2.0 with an i3-4130 CPU and 4Gb of DDR3. The GPUs are connected to the PCI-E slots using Rebbic VER009S PCI-E risers. I'm running the latest NiceHash miner and my Geforce driver is 398. This rig has been performing flawlessly for about 6 months... until this past week. When I start mining, things usually (though not always) run smoothly for a few minutes. Then, some error will flash in the output window in red, and the excavator will stop and relaunch. Sometimes the it will then mine for a few minutes before the same thing repeats. When it first started, the error message said something to the effect of "CUDA memory error using Daggerhashimoto at line 1835." I opened a support ticket with NiceHash, and they told me to disable Daggerhashimoto for the GTX 970 because it didn't have enough memory for the algorithm. I tried this, but still had the same problem... the excavator flashes an error, then restarts. So, I tried disabling the Daggerhashimoto algo for all of the cards, but I get the same behavior as before (although with different error messages). I've tried disabling each card individually in the miner and changing out PCI-E risers, but no luck. Has anyone here had similar problems where the excavator closes, then restarts, and repeats? Is there a log file that will help trouble-shoot this better?