MSI X299 XPOWER GAMING AC Quick Start Manual page 31

Multiple graphics cards installation recommendation
PCI_E1
For 44-lane CPU
PCI_E1
For 44-lane CPU
PCI_E1
PCI_E2
PCI_E3
PCI_E5
PCI_E3 PCI_E5
For 44-lane & 28-lane CPU
PCI_E1
For 28-lane CPU
PCI_E1
PCI_E2
Important
If you install a large and heavy graphics
card, you need to use a tool such as MSI
Gaming Series Graphics Card Bolster
to support its weight and to prevent
deformation of the slot.
Overview of Components
PCI_E3
PCI_E3
21