Can you try the following, use OverdriveNTool and under volt your cards just a little bit, let say 900mV and report back. If you can mine with this then you might have an PSU issue
Is there a guide out there on how to use OverdriveNTool? I have no idea on how to use it.
Any Vega guide include instructions to OverdriveNTool.
http://vega.miningguides.com/You can exclude the Vega limitations to use this software. It may fully work with the 570.
Basically is a more detailed MSI Afterburner regarding the clocks.