Thanks to everyone who posted suggestions to fix my GPU0 issue on my 4 6x470 rigs, as well as "the pill" comments.  Here's an update:

- On Saturday, I updated all 4 rigs to driver version 18.3.4 & CDM v11.6 (heard about some stability issues with 11.7).

- 2 days later, 3 of the 4 rigs are running perfectly with no GPU0/OpenCL fail restart issues. the 4th rig crashes about 2 minutes after start of CDM 11.6, so i rolled it back to 11.5 and turned off GPU0. However, this has been my problem rig for quite some time, so I am pretty sure i either have a finicky GPU or a bad riser, which I will try to address soon.

- For the first few hours, on the 3 other rigs, I did have a weird thing occuring in that GPU0 on each rig would drop down to 2-6 Mh/s sporadically.  It usually fixed itself within 5-10 minutes, but if I turned the GPU on/off quickly within CDM, it fixed it immediately.  It was worst of 2 of the 3 rigs, and I discovered that 1 only had 16GB of virtual memory set, so I upped that one to 32GB. The other one was at 32 and I upped it to 48.  Thing is, it didn't fix the issue right away, but overnight Sat and since, all 3 of those rigs have run at full capacity including GPU0.

- So, bottom line is, with W10 Fall Creator's Update it seems like 18.3.4 drivers & CDM 11.6 is the solution.

- On "the pill" front, i cant believe how easy that was!  I simply downloaded and ran the .exe and bam! both my 1080's instantly went from 23.5 to 34!  That's almost like getting an extra 1080 for free, so I will take it and look to donate to that dev team and this is a great tool!