Dell OptiPlex 790 (Early 2011) Desktop- User Manual

2 Cover Removing the Cover 1. Follow the procedures in Before Working Inside Your Computer . 2. Pull up the cover-release latch at the side of the computer. 3. Lift the cover upward to a 45–degree angle and remove it from the computer. Installing The Cover 1. Place the computer cover on the chassis....

3 Front Bezel Removing the Front Bezel 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Pry the front bezel retention clips away from the chassis. 4. Rotate the bezel away from the computer to release the hooks on the opposite edge of the bezel from the chas...

Installing The Front Bezel 1. Insert the hooks along the bottom edge of the front bezel into the slots on the chassis front. 2. Rotate the bezel towards the computer to engage the four front-bezel retention clips until they click into place. 3. Install the cover . 4. Follow the procedures in After W...

4 Expansion Card Removing the Expansion Card 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Rotate the release tab on the card-retention latch upward. 4. Pull the release lever away from the PCIe x16 card to release the securing tab from the dent in the ca...

Installing The Expansion Card 1. Insert the PCIe x4 card into the connector on the system board and press down to secure it in place. 2. Insert the PCIe card (if any) into the connector on the system board and press down to secure it in place. 3. Insert the PCIe x1 card (if any) into the connector o...

5 Optical Drive Removing the Optical Drive 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Remove the data cable and power cable from the back of the optical drive. 5. Slide up the optical-drive latch and then push the optical dr...

Installing The Optical Drive 1. Slide down the optical-drive latch and push the optical drive from the front towards the back of the computer. 2. Connect the data cable and power cable to the optical drive. 3. Install the front bezel . 4. Install the cover . 5. Follow the procedures in After Working...

6 Hard Drive Removing the Hard Drive 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the data cable and power cable from the back of the hard drive. 4. Press the hard-drive bracket latch towards the hard drive and lift it upward. 5. Flex the hard-dri...

9. Release the screws that secure the 2.5 inch hard drive to the underside of the hard drive bracket. Installing The Hard Drive 1. Tighten the screws to secure the 2.5 inch hard drive(s) to the hard-drive bracket. 2. Flex the hard-drive bracket and then insert the single 3.5 inch hard drive or the t...

7 Memory Removing the Memory 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Release the memory-retention clips on each side of the memory modules. 4. Lift the memory modules out of the connectors on the system board. 27

Installing The Memory 1. Insert the memory modules into the connectors on the system board. Install the memory module in the order of A1 > B1 > A2 > B2. 2. Press down on the memory modules until the retention clips spring back to secure them in place. 3. Install the cover . 4. Follow the pr...

8 Chassis Intrusion Switch Removing the Chassis Intrusion Switch 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Disconnect the intrusion-switch cable from the system board. 4. Slide the intrusion switch toward the chassis bottom and remove it from the syst...

Installing The Chassis Intrusion Switch 1. Insert the intrusion switch into the chassis rear and slide it toward the chassis top to secure it. 2. Connect the intrusion-switch cable to the system board. 3. Install the cover . 4. Follow the procedures in After Working Inside Your Computer . 30

9 Speaker Removing The Speaker 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Disconnect the speaker cable from the system board. 4. Unthread the speaker cable from the chassis clip. 5. Press down the speaker-securing tab and slide the speaker upwards to r...

Installing The Speaker 1. Press the speaker-securing tab and slide the speaker downward to secure it. 2. Thread the speaker cable into the chassis clip. 3. Connect the speaker cable to the system board. 4. Install the cover . 5. Follow the procedures in After Working Inside Your Computer . 32

10 Heat Sink And Processor Removing The Heat Sink and Processor 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Disconnect the heat-sink assembly cable from the system board. 4. Loosen the captive screws in the order: 1, 2, 3 and 4. 5. Lift the heat sink as...

Installing The Heat Sink and Processor 1. Insert the processor into the processor socket. Ensure that the processor is properly seated. 2. Lower the processor cover. 3. Press the release lever down and then move it inward to secure it with the retention hook. 4. Place the heat sink assembly into the...

11 Coin-Cell Battery Removing The Coin-Cell Battery 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Press the coin-cell battery inward to allow the battery to pop up from the socket. 4. Lift the coin-cell battery out of the computer. 37

Installing The Coin-Cell Battery 1. Place the coin-cell battery into its slot on the system board. 2. Press the coin-cell battery downwards until it is secured. 3. Install the cover . 4. Follow the procedures in After Working Inside Your Computer . 38

12 Power-Switch Cable Removing The Power-Switch Cable 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Disconnect the power-switch cable from the system board. 5. Pry the power-switch cable free. 6. Slide the power-switch cable ou...

Installing The Power-Switch Cable 1. Slide the power-switch cable in through the front of the computer. 2. Secure the power-switch cable to the chassis. 3. Connect the power-switch cable to the system board. 4. Install the front bezel . 5. Install the cover . 6. Follow the procedures in After Workin...

13 Front Thermal Sensor Removing The Front Thermal Sensor 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Disconnect the thermal-sensor cable from the system board. 5. Unthread the thermal-sensor cable from the chassis clips. 6. ...

7. Pry the thermal sensor away from the chassis front and remove. Installing The Front Thermal Sensor 1. Secure the thermal sensor to the chassis front. 2. Thread the thermal-sensor cable into the chassis clips. 3. Connect the thermal-sensor cable to the system board. 4. Install the front bezel . 5....

14 System Fan Removing The System Fan 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Disconnect the system-fan cable from the system board. 5. Unthread the system-fan cable from the chassis clips. 6. Slide the four grommets inwa...

7. Lift and remove the system fan out of the computer. 8. Pry up and remove the four grommets from the system fan. Installing The System Fan 1. Place the system fan in the chassis. 2. Pass the four grommets through the chassis and slide outwards along the grooves to secure them in place. 3. Thread t...

15 Input/Output Panel Removing The Input/Output Panel 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Disconnect the Input/Output panel or the FlyWire cable from the system board. 5. Remove the screw that secures the Input/Output...

7. Remove the Input/Output panel. Installing The Input/Output Panel 1. Insert the Input/Output panel into the slot on the chassis front. 2. Slide the Input/Output panel towards the left of the computer to secure to the chassis. 3. Tighten the screw to secure the Input/Output panel to the chassis. 4....

16 Power Supply Removing The Power Supply 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the PSU thermal sensor . 4. Disconnect the 4–pin power cable from the system board. 5. Unthread the 4–pin power cable from the chassis clips. 6. Disconnect the ...

10. Lift the power supply out of the computer. Installing The Power Supply 1. Place the power supply in the chassis and slide towards the back of the computer to secure it. 2. Tighten the screws to secure the power supply from the back of the computer. 3. Thread the 24–pin power cable into the chass...

17 System Board Removing The System Board 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Remove the front bezel . 4. Remove the hard drive . 5. Remove the expansion cards . 6. Remove the heat sink and processor . 7. Disconnect all the cables connected to t...

9. Remove the screws that secure the system board to the chassis. 10. Slide the system board towards the front of the computer. 11. Remove the system board from the chassis. Installing The System Board 1. Align the system board to the port connectors on the back of the chassis and place the system b...

18 Power Supply Unit (PSU) Thermal Sensor Removing The PSU Thermal Sensor 1. Follow the procedures in Before Working Inside Your Computer . 2. Remove the cover . 3. Disconnect the thermal-sensor cable from the system board. 4. Unthread the thermal-sensor cable from the chassis clip. 5. Pry the therm...

Installing The PSU Thermal Sensor 1. Secure the thermal sensor to the power supply. 2. Thread the thermal-sensor cable into the chassis clip. 3. Connect the thermal-sensor cable to the system board. 4. Install the cover . 5. Follow the procedures in After Working Inside Your Computer . 58

19 System Setup System Setup This computer offers you the following options: • Access System Setup by pressing <F2> • Bring up a one-time boot menu by pressing <F12> Press <F2> to enter System Setup and make changes to the user-definable settings. If you have trouble entering Syste...

benefit here is that you do not have to remember the <Ctrl><Alt><D> and <Ctrl><Alt><F10> keystrokes (although they still work). NOTE: The BIOS features an option to disable either or both of the keystroke prompts under the System Security / Post Hotkeys submenu. W...

20 Troubleshooting Diagnostic LEDs NOTE: The diagnostic LEDs only serve as an indicator of the progress through the Power-on Self-Test (POST) process. These LEDs do not indicate the problem that caused the POST routine to stop. The diagnostic LEDs are located on the front of the chassis next to the ...

Troubleshooting Steps – Clear CMOS.– Disconnect all internal and external peripherals, and restart the computer. If the computer boots, add the peripheral cards back one by one until you find the bad one. – If the problem persists, the system board / system board component is faulty. LED Power Butto...

Cause Timer-chip counter 2 failure Code 4–3–4 Cause Time-of-day clock stopped Code 4–4–1 Cause Serial or parallel port test failure Code 4–4–2 Cause Failure to decompress code to shadowed memory Code 4–4–3 Cause Math coprocessor test failure Code 4–4–4 Cause Cache test failure Error Messages Address...

21 Specifications Technical Specifications NOTE: Offerings may vary by region. For more information regarding the configuration of your computer, click Start (or Start in Windows XP) Help and Support, and then select the option to view information about your computer. Processor Processor type • Inte...

22 Contacting Dell Contacting Dell NOTE: If you do not have an active Internet connection, you can find contact information on your purchase invoice, packing slip, bill, or Dell product catalog. Dell provides several online and telephone-based support and service options. Availability varies by coun...