Thanks for getting back so quickly! Yes, those are the settings I'm using. The G4400 CPU's are on a Ubuntu dist. My 1080 Ti's get around 0.45-0.5 and my RX 570's get around 0.3.
Will the CUDA version be faster for Nvidia cards on Windows compared to Linux? I'm in the process of getting rid of Windows if possible.
RX 570 really shows only 0.3 with amdgpu-pro, it's not suitable drivers for XPM. 0.45 CPD for 1080Ti also too slow, what driver do you use? You can try this:
user@userpc:/root$ nvidia-smi
user@userpc:~$ nvidia-smi
Sun Apr 29 09:20:00 2018
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 390.48 Driver Version: 390.48 |
|-------------------------------+----------------------+----------------------+
CUDA version will bring 1-2% speedup on both OS and low CPU load for Windows.