ASROCK B650M PRO RS User Manual page 36

Expansion Slots (PCIe 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 PCIe x16 lane width graphics cards.
PCIE2 (PCIe 3.0 x16 slot) is used for PCIe x4 lane width graphics cards.
PCIe Slot Configurations
Single Graphics Card
Two Graphics Cards in
CrossFire
For a better thermal environment, please connect a chassis fan to the motherboard's
chassis fan connectors (CHA_FAN1~3/WP) when using multiple graphics cards.
32
PCIE1
Gen4x16
Gen4x16
TM
Mode
PCIE2
N/A
Gen3x4