ASROCK B550M-HDV Manual page 25

2.4 Expansion Slots (PCI Express Slots)
There are 2 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.
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 or CHA_FAN2 ) when using multiple graphics cards.
PCIE1 PCIE2
Gen4x16 Gen3x1
Gen3x16 Gen3x1
B550M-HDV
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