ASROCK X299 Taichi CLX Manual Del Usuario página 25

PCIE Slot Speed (For CPU with 48 PCIe lanes)
PCIE1
PCIE2
PCIE3
PCIE4
PCIE5
*If M.2 PCI Express modules are installed on M2_1 and M2_2, PCIE2 will be disabled.
PCIE Slot Speed (For CPU with 44 PCIe lanes)
PCIE1
PCIE2
PCIE3
PCIE4
PCIE5
*If a M.2 PCI Express module is installed on M2_1, PCIE2 will be disabled.
PCIE Slot Speed (For CPU with 28 PCIe lanes)
PCIE1
PCIE2
PCIE3
PCIE4
PCIE5
*If a M.2 PCI Express module is installed on M2_1, PCIE2 will be disabled.
x16
x8
x16
x1 (PCH)
x8
x16
x4
x16
x1 (PCH)
x8
x16
x4
x8
x1 (PCH)
N/A
X299 Taichi CLX
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