@Claymore
It seems there's a correlation between using temps/fan control from the miner and "NVML: cannot get fan speed, error 999 (an internal driver error occurred)" errors, causing application restart (worker restart in my case)
The rig is Win10 with 10*1060*6gb and and latest drivers. I'm using -mclock and -pwlim with no issues running v11.9, but as soon as I set -tt into anything it will lead to the error above within minutes.