Gigabyte X299-WU8 uses dual PEX switches to light up every slot
by from Techreport on (#41ZA2)
Intel's X299 platform offers a maximum of 44 PCIe 3.0 lanes from its accompanying CPUs, but even that might not be enough for the most demanding builders. Enter Gigabyte's X299-WU8 motherboard. This mobo uses not one, but two eye-wateringly expensive Broadcom PEX 8747 PCIe switches under its chipset heatsink to provide all four of its main PCIe 3.0 slots with 16 lanes of connectivity. If you just need to run a lot of single-slot cards, the WU8 can oblige with 16 lanes on its first slot and eight lanes to each of the remaining six PCIe slots on the board.
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