One of six GPUs has 99% Util and 0 H/s, Progress gets stuck at 99%

[m0t0]

Also it can be too high clocks for gpu/ram or too low ram clock, also PSU problems can behave like that. What I would try is just to lower clocks a bit. Besides on your card's you should get a bit higher MH/s if they are on stock clocks (1000MHz?) so maybe cooling problems occur and they start throttling clocks and this sometimes is the reason for ASIC hang.

Thanks @KT819GM,
The clocks are set to stock values, no overclocking. It is reported as 925 Mhz on each.

I have been thinking it may be related to the temp control and throttling. There did seem to be some correlation to the card hanging after its temperature increased higher relative to the others around it, but I haven't been able to reliably reproduce.

I also tested using a lower temp value --gpu-temp-retain=45 to force the fans to be 100% and while it took longer (about 8 minutes instead of 2), #4 still got stuck. The temps, while not 45 were not too hot < 60.

[logistix111]

hmm have you checked out all special settings on your motherboard ? do yoou have raizzerz for your cards, the first time i test them , was the last time i ever wanna test some...

Riser cards, if inserted properly and snug, will help you generate about 200 bitcoins my friend. At least for me back in 2012 they did. Nearly a quarter million dollars, doing nothing, with free electricity from the datacenter I worked at... Otherwise, you are selling yourself short with PCIe slot real estate and/or more money spent on water cooling. There are some fancy USB 3.0 cable riser cables now that are even better (for air flow and mobility)

M0t0, perhaps you can update the BIOS on your motherboard as well as the GPUs themselves? Perhaps you can try inserting them in different slots? Are you sure each card is getting enough voltage/wattage?