Expansion Slots (Pci Express Slots) - ASROCK X299 Taichi XE Manual

2.4 Expansion Slots (PCI Express Slots)

There are 5 PCI Express slots on the motherboard.
Before installing an expansion card, please make sure that the power supply is switched off
or the power cord is unplugged. Please read the documentation of the expansion card and
make necessary hardware settings for the card before you start the installation.
PCIe slots:
PCIE1 (PCIe 3.0 x16 slot) is used for PCI Express x16 lane width graphics cards.
PCIE2 (PCIe 3.0 x16 slot) is used for PCI Express x8 lane width graphics cards.
PCIE3 (PCIe 3.0 x16 slot) is used for PCI Express x16 lane width graphics cards.
PCIE4 (PCIe 2.0 x1 slot) is used for PCI Express x1 lane width cards.
PCIE5 (PCIe 3.0 x16 slot) is used for PCI Express x8 lane width graphics cards.
* If you install CPU with 44 lanes, PCIE1/PCIE2/PCIE3/PCIE5 will run at x16/x8/
x16/x0 or x8/x8/x16/x8.
* If you install CPU with 28 lanes, PCIE1/PCIE2/PCIE3/PCIE5 will run at x16/x0/
x8/x0 or x8/x0/x8/x8.
* If you install CPU with 16 lanes, PCIE1/PCIE2/PCIE3/PCIE5 will run at x16/x0/
x0/x0 or x8/x0/x4/x0.
PCIe Slot Configurations (For CPU with 44 PCIe lanes)
Single Graphics Card
Two Graphics Cards in
CrossFireX TM
Mode
Three Graphics Cards in
3-Way CrossFireX
or 3-Way SLI TM
20
PCIE1
x16
or SLI TM
x16
TM
Mode x8
Mode
PCIE2 PCIE3 PCIE4
N/A N/A
N/A x16
N/A x16
PCIE5 M2_1
N/A N/A
N/A N/A
N/A x8
x4
x4
x4