Quote from: Bigdrago on January 15, 2018, 06:30:42 PM

"There should be no need for update, this board should support 19 cards already. To run more than 8 AMD cards, you will need AMD Radeon Software Crimson ReLive Edition 17.10.2 driver. Please download this from AMD website. For full 19 cards, for system stability we recommend mix of AMD and NVidia cards, refer to manual page 1-9 onward for details."

I bet it was some clueless blonde from the support team who is not aware of any nuances and only checked the manual with one eye and gave you such "help".

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So. Hard to say if it is the mb or os that is only capable of 13 gpus.

You don't need any OS just to start the motherboard. It does not start with 14 ordinary GPUs.