Epson Epson - Manual (Page 104)

Installing the Hard Disk Drive
Before you install the hard disk drive, turn it over so you can
see the circuit board, as shown below. Locate the side of the
drive connector containing pin 1, indicated by a “1” or “2”
printed on the board. You need to know the location of pin 1
when you connect the hard drive cable.
win 1
Follow these steps to install a hard disk drive in the mounting
bracket:
1. With the drive components facing down, slide the drive into
the bracket until the front of the drive is nearly flush with
the edge of the bracket.
5-6 Installing and Removing Slimline Drives