Make sure your AMD Gaming Evolve app didn't automatically update your drivers, I had to use DDU and reinstall 4 times until I figured out it does that EVEN IF you uncheck the box during installation. You have to manually open AMD Gaming Evolved, click on the wheel besides deriver update and uncheck auto updates.
That's not it. And this is a 100% clean and updated Windows 10 x64 install with 4GB ram, 20 GB virtual mem, and NOTHING but AMD 16.3 drivers and claymore installed. Blows my damn mind.
General behavior is:
1. A card (random) will hash at 0% while all others are fine
2. OpenCL call hangs.
3. Crash
Sometimes all cards will be hashing just dandy for a minute or two, then one drops, then OpenCL call fail on 1 card.
Experience has shown me that the OpenCL hang for any of my rigs (I am small time with 16 rigs) is that it is one of three things:
1. Video drivers need to be re-installed. I have been using 16.11.5 for all my rigs for several months now without issue, or at least with the least number of issues. Install it with only one card connected to the motherboard, and then add the other cards and let them auto-populate/auto-install. This is probably 50% of my issues.
2. I run a mod'd bios on all my cards that I make that uses the #5 voltage strap across #6 and #7 straps and runs the mem speed at 1750 Mhz. Sometimes this causes the voltage to be too low on the #7 strap and I have to raise that voltage up in 20 mV steps until I get it stable, and then I will flash the bios with that change, or you can use WattTool or whatever you have to make that change. None of the cards are exactly the same due to variations in manufacturing even though they are all the same make and model, so getting the voltage right is key. This is probably 40% of my issues.
3. Bad riser cards or bad riser cables, or a bad connection to the motherboard. This has only happened twice in 6 months, but it is a possible contributor on a less frequent case.
A few times I have had to do a complete Windows 10 clean install, but I have come to realize that most of the issues are really video drivers and undervolting the GPU core clock. Hope this helps.