https://www.techpowerup.com/239484/a...-19-pcie-slots

ASUS dropped its hat into the DIY crypto-currency mining hardware craze, with the introduction of the B250 Mining Expert motherboard. This ATX form-factor motherboard comes with a jaw-dropping eighteen PCI-Express gen 3.0 x1 slots, in addition to a PCI-Express gen 3.0 x16, taking full advantage of the 200-series platform's PCIe lane budget. The board draws power from three 24-pin ATX, one 8-pin EPS, and three 4-pin Molex connectors, although besides one ATX and EPS, the other connectors are optional for the machine to start, but required for some of those PCIe slots to work.

Based on the Intel B250 Express chipset, the board supports 6th and 7th generation "Skylake" and "Kaby Lake" processors. The rest of the board is pretty spartan, with just enough connectivity to make the machine work. You get two DDR4 DIMM slots supporting up to 32 GB of dual-channel memory, four SATA 6 Gbps ports, six USB 3.0 ports (two via header), a gigabit Ethernet connection, 6-channel HD audio, HDMI display output, and legacy PS/2 connectors. The company didn't reveal pricing.
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