Dell OptiPlex 7490 All-In-One Service Manual
Summary
The Dell OptiPlex 7490 All-In-One Service Manual with regulatory model W26C provides comprehensive repair instructions for this business desktop. It covers electrostatic discharge (ESD) protection, ESD field service kit requirements, and step-by-step component removal and installation. Technicians servicing the OptiPlex 7490 AIO can reference this guide for safe handling of sensitive components, display assembly procedures, and internal module replacement on this compact form factor.
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Opti Plex 7490 All-In-One Service Manual
Regulatory Model: W26C Regulatory Type: W26C003/W26C004 August 2021 Rev. A01
Page Summary Contents For Dell OptiPlex 7490 All-In-One Service Manual
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Opti Plex 7490 All-In-One Service Manual Regulatory Model: W26C Regulatory Type: W26C003/W26C004 August 2021 Rev. A01
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Notes, cautions, and warnings NOTE: A NOTE indicates important information that helps you make better use of your product. CAUTION: A CAUTION indicates either potential damage to hardware or loss of d...
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Contents Chapter 1: Working inside your computer...................................................................................... Safety instructions.................................................
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Removing the coin-cell battery................................................................................................................................ Installing the coin-cell battery............
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Removing the display panel.......................................................................................................................................79 Installing the display panel...........
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Working inside your computer Safety instructions Use the following safety guidelines to protect your computer from potential damage and to ensure your personal safety. Unless otherwise noted, each pro...
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2. Shut down your computer. Click Start > Power > Shut down. NOTE: If you are using a different operating system, see the documentation of your operating system for shut-down instructions. 3. Di...
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the damage. The weakened trace may take weeks or months to melt, and in the meantime may cause degradation of memory integrity, intermittent memory errors, etc. Perform the following steps to prevent ...
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ESD protection summary It is recommended that all field service technicians use the traditional wired ESD grounding wrist strap and protective anti-static mat at all times when servicing Dell products...
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Removing and installing components NOTE: The images in this document may differ from your computer depending on the configuration you ordered. Recommended tools The procedures in this document may req...
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Table 1. Opti Plex 7490 All-in-One screw list (continued) Component Screw type Quantity Screw image Camera assembly M3x5 Camera door M3x5 Heat sink—UMA Captive screws Heat sink—Discrete Captive screws...
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Major components of your computer 1. Stand 2. Bottom cover 3. Heat sink 4. Processor fan 5. Processor 6. Memory module 7. M.2 2230/2280 solid-state drive 8. Rear-I/O bracket 9. Side-I/O board 10. Spea...
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22. Back cover Stand Removing the fixed stand Prerequisites 1. Follow the procedure in Before working inside your computer. CAUTION: When servicing the system, place it on an elevated, clean, and flat...
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Installing the fixed stand Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image provides a vi...
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About this task The following image provides a visual representation of the articulating stand removal procedure. Removing and installing components
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Steps 1. Press and slide the release button up. 2. Hold the button in the release position, and lift the stand upward. 3. Slide the stand downward, to lift the stand off the back cover. 4. Pry the rub...
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Steps 1. Align the rubber feet with the slots on the bottom cover and push it firmly in place. 2. Align the tabs on the stand with the slots on the back cover. 3. Snap the stand until it clicks into p...
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Steps 1. Press and slide the release button up. 2. Hold the button in the release position, and lift the stand upward. 3. Slide the stand downward, to lift the stand off the back cover. Installing the...
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Steps 1. Align the tabs on the stand with the slots on the back cover. 2. Slide the stand upward until it clicks into place. Next steps 1. Follow the procedure in After working inside your computer. C...
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Steps 1. Unroute the power cable from the slots on the cable cover. 2. Remove the screw (M3x9) that secures the cable cover to the bottom cover. 3. Lift the cable cover from the bottom cover. Removing...
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Installing the cable cover Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image provides a vi...
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Steps 1. Route the power cable through the slots on the cable cover. 2. Align the screw hole on the cable cover with the screw hole on the bottom cover. 3. Replace the screw (M3x9) to secure the cable...
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Steps 1. Press and hold the release tab on the back cover to release it from the latch on the system-board shield. 2. Slide the back cover up to release the tabs on the cover from the slots on the mid...
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Installing the back cover Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image provides a vis...
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Steps 1. Place the back cover on the middle frame and system-board shield and align the tabs on the back cover with the slots on the middle frame. 2. Slide the back cover to lock the release tab under...
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Steps 1. Press down the tab securing the hard-drive assembly to the system-board shield. 2. Slide and lift the hard-drive assembly from the slot on the display-assembly base. 3. Pry the tabs on hard-d...
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Steps 1. Align the tabs on the hard-drive bracket with the slots on the hard drive. 2. Flex the hard-drive bracket and replace the remaining tabs on the hard-drive bracket with the slots on the hard d...
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Steps 1. Pry and remove the DIMM door from the system-board shield. 2. Using your fingertips, spread apart the securing clips on the memory-module slot until the memory module pops up. 3. Slide and re...
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Steps 1. Align the notch on the memory module with the tab on the memory-module slot. 2. Slide the memory module firmly into the slot at an angle and press the memory module down until it clicks into ...
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Steps 1. Remove the five screws (M3x5) that secure the system-board shield to the display-assembly base. 2. Lift the system-board shield off the display-assembly base. Installing the system-board shie...
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Steps 1. Align the screw holes on the system-board shield with the screw holes on the display-assembly base. 2. Replace the five screws (M3x5) to secure the system-board shield to the display-assembly...
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About this task The following image indicates the location of the M.2 2230 solid-state drive and provides a visual representation of the removal procedure. Steps 1. Remove the screw (M2x2.5) that secu...
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Steps 1. Align the notch on the solid-state drive with the tab on the M.2 card slot. 2. Slide the solid-state drive into the M.2 card slot on the system board. 3. Replace the screw (M2x2.5) to secure ...
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Steps 1. Remove the screw (M2x2.5) that secures the solid-state drive to the system board. 2. Slide and remove the solid-state drive from the M.2 card slot on the system board. Installing the M.2 2280...
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Steps 1. Align the notch on the solid-state drive with the tab on the M.2 card slot. 2. Slide the solid-state drive into the M.2 card slot on the system board. 3. Replace the screw (M2x2.5) to secure ...
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Steps 1. Disconnect the system-fan cable from the system board. 2. Remove the three screws (M3x5) that secure the system fan to the display-assembly base. 3. Lift the system fan, along with its cable,...
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Steps 1. Align the screw holes on the system fan with the screw holes on the display-assembly base. 2. Replace the three screws (M3x5) to secure the system fan to the display-assembly base. 3. Connect...
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Steps 1. Using the plastic scribe, press on the metal clip to release the coin-cell battery from the coin-cell battery holder. 2. Lift the coin-cell battery from the coin-cell battery holder. Installi...
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Steps With the positive-side facing up, insert the coin-cell battery into the battery holder on the system board and gently press the battery until it snaps into place. Next steps 1. Install the syste...
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Steps 1. Remove the two screws (M2x2.5) that secure the wireless-card shield to the system board. 2. Unroute the antenna cables from the routing guides on the wireless-card shield. 3. Lift the wireles...
Manual Details
| Brand | Dell |
|---|---|
| Pages | 106 |
| File Size | 35.16 MB |
| Published | June 28, 2026 |
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Frequently Asked Questions
What should I do before working inside the computer?
Follow safety precautions, specifically regarding electrostatic discharge (ESD) protection.
How can I troubleshoot a computer issue?
Visit www.dell.com/support or use the My Dell app for self-help resources, and enter your Service Tag there.
What is the procedure for flea power release?
Turn off the unit, disconnect the adapter, press and hold the power button for 15 seconds, then reconnect and turn it on.
Which resources can I use for online help with the OS?
Use www.dell.com/support/windows for top solutions, diagnostics, drivers, and downloads.