HP Laserjet p3015 - Manual (Page 147)

Install EIO cards
Install an EIO card
1. Turn off the product.
2. Remove the two screws and cover plate from the EIO slot on the back of the product.
3. Install the EIO card in the EIO slot and tighten the screws.
ENWW Install memory, internal USB devices, and external I/O cards 135