Dell OptiPlex 390 Desktop Computer User Manual

Product Overview and Form Factors

The Dell OptiPlex 390 is a flexible commercial desktop computer powered by 2nd Generation Intel Core processors and the Intel H61 Express chipset. Designed for office productivity and enterprise deployments, the system is manufactured in three distinct chassis sizes: Mini Tower (MT), Desktop (DT), and Small Form Factor (SFF).

• Mini Tower (MT): Offers maximum expansion with support for four drive bays, four full-height PCIe expansion slots, and dual optical drives.

• Desktop (DT): Balances space savings and expandability with support for four low-profile expansion slots and two drive bays.

• Small Form Factor (SFF): Compact footprint suitable for desk placement or all-in-one stand mounting, supporting two low-profile expansion slots and two bays.

Controls and External Connections

The front and rear panels provide essential input/output ports, audio connectors, and system status indicators across all chassis form factors.

• Front Power Button and Status LED: Powers the system on or off and indicates power status.

• Front Optical Drive: Optional SATA optical drive bay equipped with a mechanical eject button.

• Front Audio Ports: 3.5 mm microphone connector and 3.5 mm stereo headphone jack.

• Front USB Ports: Two external USB 2.0 ports for convenient peripheral connections.

• Rear Video Interfaces: One 15-pin VGA port and one HDMI video output for single or dual monitor setups.

• Rear USB Ports: Six USB 2.0 ports for external storage, input devices, and accessories.

• Network Interface: Integrated RJ-45 Gigabit Ethernet port with link integrity and activity LEDs.

• Rear Audio Connectors: Three color-coded 3.5 mm jacks for audio line-in, audio line-out, and microphone.

• Power Input and Diagnostic: AC power receptacle, power supply self-test diagnostic LED, and self-test push button.

Setup and Cable Connections

Follow these step-by-step procedures to unpack, connect, and power on your Dell OptiPlex 390 desktop system.

1. Place the computer on a stable, level surface ensuring ventilation grilles on the front, sides, and rear remain unobstructed by at least 10 cm.

2. Connect the display cable from your monitor to the integrated VGA or HDMI port on the back panel.

3. Plug the USB keyboard and USB mouse into the rear USB 2.0 ports.

4. Connect an RJ-45 Ethernet network cable from your local network switch or router to the rear Gigabit Ethernet port.

5. Plug the AC power cord securely into the rear power connector of the power supply unit, then connect the other end to a grounded wall outlet.

6. Turn on the display monitor, then press the front panel power button on the computer to initiate boot-up.

System Diagnostics and Status Indicators

The OptiPlex 390 features built-in diagnostics via the front power button LED, diagnostic numbered LEDs (1 through 4), and the power supply self-test light.

Hardware Maintenance and Jumper Reset Procedures

Internal hardware upgrades and BIOS settings resets can be performed directly on the system board by clearing flea power and manipulating the maintenance jumpers.

1. Shut down the computer through the operating system and disconnect the AC power cord from the wall outlet.

2. Press and hold the front power button for 5 seconds while unplugged to discharge residual electrical flea power.

3. Release the side panel latch and remove the chassis side cover.

4. Locate the 2-pin password jumper marked PSWD and the 2-pin real-time clock reset jumper marked RTCRST on the system board.

5. To reset BIOS configuration settings to defaults: Remove the 2-pin plug from the PSWD pins, place it across the RTCRST pins for 5 to 10 seconds, then return it to the PSWD pins.

6. To clear forgotten BIOS passwords: Remove the 2-pin jumper plug from the PSWD pins, boot the computer once without the plug to clear password locks, then power off and reinstall the jumper plug.

7. Reattach the chassis side cover, reconnect external cables and power, and boot into system setup (F2) to adjust settings.

Technical Specifications

Detailed physical, electrical, and hardware architectural specifications for the Dell OptiPlex 390 family.