PCIe Riser, Ubit PCI-E Riser for Bitcoin Litecoin ETH Coin Mining Dual-6PIN+MOLEX Powered PCIE Extension Cable GPU Riser PCIEX1 to PCIE X16 GPU Riser. 4PIN(MOLEX), and two Graphic card 6PIN interface (two 6PIN interface directing differently) are optional to power, which provides Graphic card independent power and reduces motherboard burden when using more Graphic cards.
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