Nvidia Mellanox ConnectX-6 Dx Series User Manual page 23

Step 2: Applying even pressure at both corners of the card, insert the adapter card in a PCI
Express slot until firmly seated.

Do not use excessive force when seating the card, as this may damage the chassis.
Secure the adapter card to the chassis.
Step 1: Secure the bracket to the chassis with the bracket screw.
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