Detent for retention of information handling resource

An information handling system, comprising:

• a motherboard comprising a mechanical post extending from a surface of the motherboard;
• and
• a riser card assembly comprising:
• a circuit board;
• a cable configured to communicatively couple the circuit board to the motherboard;
• a connector configured to receive an expansion card to communicatively couple the expansion card to the motherboard;
• and
• a detent assembly configured to mechanically couple the riser card assembly to the motherboard, the detent assembly comprising:
• a pin mechanically coupled to a surface of the riser card assembly and extending from the surface of the riser card assembly and configured to mechanically engage with a first feature of the mechanical post in order to align the riser card assembly to the motherboard;
• and
• a detent mechanically coupled to the pin and having an annular shape, the detent configured to mechanically engage with a second feature of the mechanical post in order to mechanically retain the riser card assembly with the motherboard.