HP AFICIO SP 8100DN - Manual (Page 28)

Attaching User Account Enhance Unit Type E
17
2
D
Remove the screws as shown by turning them counterclockwise using the
provided screwdriver.
E
Hold the part (1) of the controller board, and then slide it out completely.
F
Place the controller board on a flat surface.
AQV500S
AQV501S
AQV516S