The key feature of this ATX motherboard are its nineteen (!) PCI Expres slots. There is one full-size PCI Express x16 slot, the other 18 are PCIe x1 slots that are designed to be used in combination with PCIe risers.
One important caveat is that ASUS notes that support for 19 video cards is still in the works, that feature will be added via a driver update before the end of the year. At the moment, the motherboard supports a maximum of eight GPUs.
ASUS B250 Mining Expert is the world's first mining motherboard to feature 19 PCI Express® (PCIe®) slots. With 18 PCIe x1 and one PCIe x16 slots on board, plus three zoned ATX12V power connectors, B250 Mining Expert lets you run up to 19* NVIDIA or AMD GPUs in parallel to max out your megahash rates!The B250 Mining Expert is sold in Europe for 170.50EUR.
* B250 Mining Expert currently supports a total of up to eight NVIDIA and AMD GPUs. An unlimited number of GPUs will be supported following a driver update that is planned for Q4 2017.