HP Vectra VE 4/xx User Manual page 53

unscrew the side panel and slide it away from the computer
connect the accessory board's cable to the VESA pass-through connector on the
system board
To activate the VESA pass-through connector, the DOS file FCON.EXE must be
executed.
9. Install any other accessories, then refer to "Checking the Installation" to complete the
installation.
HP Vectra PC User's Guide 3 Installing Accessories In Your PC 53