ASROCK B550 Phantom Gaming-ITX/ax Manual page 29

2.4 Expansion Slot (PCI Express Slot)
There is 1 PCI Express slot 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.
PCIe Slot Configurations
Ryzen Series CPUs (Matisse)
Ryzen Series APUs (Renoir)
For a better thermal environment, please connect a chassis fan to the motherboard's
chassis fan connector (CHA_FAN1/WP) when using multiple graphics cards.
B550 Phantom Gaming-ITX/ax
PCIE1
Gen4x16
Gen3x16
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