Well I can confirm that 5 gpus (1060's) on powered risers work in the ab350 pro4 and Windows 10. No bios settings helped but a few of nvidia driver re-installs and trial and error got it going. To outline the process I used and re-did a few times to make sure...
(note: best to start with no drivers installed so clean that up first)
(note2: Windows 10 worked Windows 7 didn't although I didn't try this method as long on Win7)
1. cards in risers for slots 1 and 2
2. boot and install drivers
3. restart.
4. shutdown
5. cards in risers for slots 4 and 5
6. boot and make sure all 4 appear under display adapters with 2 showing warning for needing a restart
7. reboot to make windows will boot with 4 cards recognized.
The last one was tricky and took a few tries to be honest.
8. card in riser in slot 6.
9. during the boot and after the windows logo appears and the bubbles are circling below , unplug the usb from the adapter that is in slot 6 and let it finish booting to windows.
10. look in the device setting again and you should see a 5th entry in display adapters with a warning like in step 6 or a new entry under "other" for a VGA adapter.
11. plug the usb back into the adapter and in device settings "re-scan for changes" and make sure a 5th entry is still under display adapters.
12. restart and you should be good to go with 5...which is better than 4
Hopefully this all work for someone. It took me 3 iterations of complete driver uninstalls and re-installs to get it to where I could consistently
I can overclock all cards with MSI afterburner and my eth miner has been running for +24 hr at this point.
I might work on getting the 6th card going but that 3rd slot really doesn't seem to want to work.
Thanks for the update!!! I will try this when my new risers come in.. Keep us updated if you get that 6th card to work.
Show Posts
i found 4 now 
before the ico's when ppl had to work "mine" to get their coins.. 
