MSI MEG Z790 ACE Manuel D'utilisation page 34

PCI_E1~3: PCIe Expansion Slots
BAT1
⚠
Important
If you install a large and heavy graphics card, you need to use a tool such as MSI
∙
Graphics Card Bolster to support its weight to prevent deformation of the slot.
For a single PCIe x16 expansion card installation with optimum performance, using
∙
the PCI_E1 slot is recommended.
∙ When adding or removing expansion cards, always turn off the power supply and
unplug the power supply power cable from the power outlet. Read the expansion
card's documentation to check for any necessary additional hardware or software
changes.
PCI_E1 slot will run at x8 speed when installing device in the PCI_E2 slot or M2_4
∙
slot.
M2_4 slot will be unavailable when installing in the PCI_E2 slot.
∙
Multiple graphics cards installation recommendation
x16
PCI_E1: PCIe 5.0 x16 (From CPU)
PCI_E2: PCIe 5.0 x8 (From CPU)
PCI_E3: PCIe 4.0 x4 (From Z790 chipset)
x8
x8
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