Stap 7 vertalen
This part is a bit tricky, because you need to connect the mainboard onto PCI riser card as you slide it in.
First, place mainboard's connectors on the I/O shield at an angle, as shown in the first photo. Then gently push the left edge of the board and check if the riser card is properly mating with the PCI slot (green arrows in the second photo). If it's OK, push the mainboard all the way onto the hexagonal mounting posts and secure it with screws.