The 5x V006 PCIe riser boards didn't even power up the GPU's (tried direct 4pin molex and sata to 4pin adapters and even new USB cables) so i suspect that entire batch was faulty but the V007S ones all worked without issue.
I actually have a B350-BTC where I'm fairly certain I'm having the same riser issues as you. Curious where you got your batch of V006 risers from, and where you ordered the working replacements.
I have a new set on the way of 006C's as well to try, but wouldn't mind stocking some known working spares to have on the way just in case.
It was an eBay seller in Australia that listed them as local stock but they came from China and i had to email them a video of the fault to
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