ASROCK B550M Phantom Gaming 4 Manual page 27

2.4 Expansion Slots (PCI Express Slots)
There are 3 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 4.0 x16 slot) is used for PCI Express x16 lane width graphics cards.
PCIE2 (PCIe 3.0 x1 slot) is used for PCI Express x1 lane width cards.
PCIE3 (PCIe 3.0 x16 slot) is used for PCI Express x4 lane width graphics cards.
PCIe Slot Configurations
Ryzen Series CPUs (Matisse)
Ryzen Series CPUs (Renoir)
For a better thermal environment, please connect a chassis fan to the motherboard's
chassis fan connector (CHA_FAN1/WP, CHA_FAN2/WP or CHA_FAN3/WP) when using
multiple graphics cards.
B550M Phantom Gaming 4
PCIE1 PCIE2
Gen4x16 Gen3x1
Gen3x16 Gen3x1
PCIE3
Gen3x4
Gen3x4
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