Finally got my ethminer to recognize and mine on both my R9 290Ss. 25mh each. So happy days...
Now they won't, but at least ethminer still sees both my cards....
Lets back track for a second...
I had set my GPUs into crossfire after banging my head for days trying everything for both to even be seen. Second card was always just a ghost untill crossfire was enabled.. Also crossfire never seemed to effect my expected hashrate..
So then I tried to remove crossfire, and back to the beginning I was with only lspci seeing both cards and nothing else.
Set them back to crossfire mode for OpenCL to recognize I have them both attached, and sure enough ethminer sees them too.
But.. Ethminer will sometimes benchmark correct scores, but normally will do one of two things.. Mine 00MH then hang, or bail because it thinks the memory size is too small for the DAG. Sometimes it doesn't like Geth's DAG file and will create it's own on each card.
Side note: Catalyst always sees my second cards and lists them correctly in terminal, but the GUI calls my second card [unidentified]R9 200 card... No matter what the circumstances.
I have reason to believe that problems occur because both GPUs are identical and no PCI ID gets assigned in OpenCl unless catalyst forces identification when crossfire is enabled. But it could also be environment settings, but I've tried export DISPLAY=0 , export GPU_MAX_ALLOC_PERCENT=98. It could also be that the motherboard has an unsupported APU chipset (HD 3300) that isn't used because there is no driver attached; so the AMD processor gets defined as an OpenCL platform in device position 1 (the position my second GPU takes in crossfire). I also wonder if it is the GPU BIOSs, both cards hold the same ID (I assume) and the cards have no Uber or Slow setting (factory overclocked with unlocked voltage). Apparently both switch positions yield the same BIOS settings.
Catalyst 15.07 (I think) (sudo apt-get install fglrx fglrx-updates fglrx-dev-updates)
Installed all the dependencies
Tied the AMDAPPSDK folders and libraries in /opt as stated in the frontier manual
For what it's worth I have installed the ./print-devices MIT program (very helpful)
And not sure if it is an issue, I installed Steam
Nothing seemed to get catalyst to properly identify the second card even in crossfire. multi-head setups failed, --initial=all didin't seem to do anything, force Xinerama, --initial=0,2.. only crossfire
Yes I set ethminer to --no-precompute (still would make a DAG if it didn't like the Geth made DAG)
Yes I targeted the --opencl-device # to the specific GPU in separate terminal windows
Yes the --rpc flag was set, and yes startautoDAG was set to true