[. . . ] Only technicians authorized by NEC Computers International BV should attempt to repair this equipment. All troubleshooting and repair procedures are detailed to allow only subassembly/module level repair. [. . . ] be sure to connect the wrist wrap to an unpainted metal portion of the computer chassis. As an alternative, you can dissipate electrostatic buildup by touching an unpainted metal portion of the computer chassis with one hand. Then touch the device you are (un)installing with the other hand, and maintain continuous contact with it until it is (un)installed in the computer. Under no circumstances should you attempt to disassemble the power supply. Inside the power supply are hazardous voltages that can cause serious personal injury. Carefully slide the side panel towards the back and pull it away from the chassis. With one hand grip the notch at the bottom of the front bezel and firmly pull it away. To remove the DVD/CD-ROM drive, first open the chassis (see section Opening the Chassis) and remove the front bezel (see section Removing the Front Bezel), then follow the steps below: 1. To remove the floppy disk drive, first open the chassis (see section Opening the Chassis) and remove the front bezel (see section Removing the Front Bezel), then follow the steps below: To remove the hard disk drive, first open the chassis (see section Opening the Chassis) and remove the front bezel (see section Removing the Front Bezel), then follow the steps below: 1. Carefully disconnect the four-wire power cable and the flat data interface cable from the hard disk drive. Remove the four screws (two on either side) from the bay and take out the hard disk drive. To remove add-in cards, first open the chassis (see section Opening the Chassis), remove the front bezel (see section Removing the Front Bezel), and follow the steps below: 1. [. . . ] Note: When reassembling the power supply, make sure that the voltage selector switch is set correctly before connecting the system to a power strip (surge protector) or grounded AC electrical outlet. If the switch is set incorrectly, the system could become seriously damaged. [. . . ]