I was on vertminer 0.5.3 from the start. Also it is not related to fixed fan because my 280X had fan set to something like 60-90 and they had the same problem.
Sorry, i was not exact enough.
From my understanding you use the fan settings from the miner even if fixed or within a defined range, correct?
With 0.5.3 i patched the miner with a ADL6 patch for R9 cards from the litecoin forum.
There are no known issues with this patch, it does only prevent a system crash after exiting the miner when a R9 290/290X is used.
I will check if there is a relation but without a proper use case how to provoke this issue it will be hard to find.
It is always a bad idea to use hardware control from within a piece of software (not only related to the miner).
Because if the SW crashes your hardware is not safe (crash = undefined state). Also there can be (unkown) SW errors.
Using the BIOS is safe but normally also louder.