.... But I would also expect the symptoms you describe with an overheat, and I'm not seeing them. No increasing temps, no "x"s on the chips, HW errors still negligible. Fan speeds are dropping, now 1800-1900, down from 2200-2300. So the unit is getting cooler as it slows down. .... ...
There, my friend, is the sign you are looking for!
Fan speeds dropping ... unit is getting coolerThat means there are some chips that have gone offline!
EDIT: Either that, or the chips are not getting work ..... now you see how that the queue argument was formented in my mind?
Does it? Why are all chips still reporting "o" and not "-" or "x"? That is why I'm wondering about the internal throttling. There should be plenty of work, I have tried leaving queue at default as well as deleting queue parameter completely. I have not tried --queue 1024 yet though. But I saw the same result with two different pools and with and without deletion of the parameter.
New test run started: 1024 firmware, 250/0750, queue left at stock, cgminer left at stock. Only change to stock is the additional options in cgminer.lua, which do not change the 250 values.