ASROCK H81M-VG4 R4.0 Handbuch Seite 18

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 2.0 x1 slot) is used for PCI Express x1 lane width cards.
PCIE2 (PCIe 2.0 x16 slot) is used for PCI Express x16 lane width graphics
cards.
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