Lenovo ThinkCentre M90a Gen 3 User manual

M90a Gen 5
User Guide

Read this first
Before using this documentation and the product it supports, ensure that you read and understand the
following:
• Safety and Warranty Guide
• Generic Safety and Compliance Notices
• Setup Guide
First Edition (January 2024)
© Copyright Lenovo 2024.
L M TED AND RESTR CTED R GHTS NOT CE: f data or software is delivered pursuant to a General Services
Administration “GSA” contract, use, reproduction, or disclosure is subject to restrictions set forth in Contract No. GS-
35F-05925.

Contents
About this documentation . . . . . . . . . . . . ii
Chapter 1. eet your computer . . . . . 1
Front . . . . . . . . . . . . . . . . . . . . 1
Rear . . . . . . . . . . . . . . . . . . . . 3
Specifications . . . . . . . . . . . . . . . . 5
USB specifications . . . . . . . . . . . . . . 6
The Vantage app . . . . . . . . . . . . . . . 7
Chapter 2. Get started with your
computer . . . . . . . . . . . . . . . . . 9
Access networks . . . . . . . . . . . . . . . 9
Adjust the computer stand (for selected models) . . 10
Rotate the monitor (for selected models) . . . . . 11
Adjust the tiltable camera (for selected models) . . 12
Use the touch screen (for selected models) . . . . 12
Connect an external display . . . . . . . . . . 14
Transfer data . . . . . . . . . . . . . . . . 14
Privacy (for selected models) . . . . . . . . . 15
Connect to a Bluetooth device . . . . . . . . . 16
Conventional pair . . . . . . . . . . . . 16
Swift pair . . . . . . . . . . . . . . . 16
CE performance mode . . . . . . . . . . . . 16
Smart power-on feature (for selected models) . . . 17
Set the power plan . . . . . . . . . . . . . 17
Security . . . . . . . . . . . . . . . . . . 17
Lock the computer . . . . . . . . . . . . 18
Smart USB protection . . . . . . . . . . 18
Use software security solutions . . . . . . . 18
Chapter 3. UEFI BIOS . . . . . . . . . 21
Enter the UEF B OS menu . . . . . . . . . . 21
Navigate the UEF B OS menu . . . . . . . . . 21
Enable or disable the ErP LPS compliance mode . . 21
Update the UEF B OS . . . . . . . . . . . . 22
From the Vantage app . . . . . . . . . . 22
From the Lenovo Support Web site . . . . . 22
From the Windows Update . . . . . . . . 22
Chapter 4. CRU replacement . . . . . 23
CRU list . . . . . . . . . . . . . . . . . . 23
Computer stand. . . . . . . . . . . . . . . 24
Rear /O cover . . . . . . . . . . . . . . . 29
System board shield . . . . . . . . . . . . . 30
Primary hard disk drive . . . . . . . . . . . . 31
Optical drive . . . . . . . . . . . . . . . . 31
Secondary hard disk drive and bracket. . . . . . 33
M.2 solid-state drive . . . . . . . . . . . . . 34
Memory module . . . . . . . . . . . . . . 35
Chapter 5. Help and support . . . . . 37
Find your serial number . . . . . . . . . . . . 37
Diagnose and troubleshoot your computer . . . . 37
Troubleshoot and diagnose at Lenovo
Support Web site . . . . . . . . . . . . 37
Hardware scan . . . . . . . . . . . . . 38
Recover Windows operating system. . . . . . . 38
Call Lenovo . . . . . . . . . . . . . . . . 39
Before you contact Lenovo . . . . . . . . 39
Self-help resources . . . . . . . . . . . . . 39
Purchase accessories or additional services . . . 39
Appendix A. Notices and
trademarks . . . . . . . . . . . . . . . 41
© Copyright Lenovo 2024 i

About this documentation
• This guide applies to the Lenovo product models listed below. llustrations in this guide may look slightly
different from your product model.
odel name achine types ( T)
ThinkCentre M90a Gen 5 12SH, 12SK, 12SL, 12SM, 12SN
• For further compliance information, refer to the Generic Safety and Compliance Notices at https://
pcsupport.lenovo.com/docs/generic_notices.
• Depending on the model, some optional accessories, features, and software programs might not be
available on your computer.
• Depending on the version of the operating systems and programs, some user interface instructions might
not be applicable to your computer.
• Documentation content is subject to change without notice. Lenovo makes constant improvements to the
documentation of your computer, including this User Guide. To get the latest documentation, go to https://
pcsupport.lenovo.com.
• Microsoft® makes periodic feature changes to the Windows® operating system through Windows Update.
As a result, some information in this documentation might become outdated. Refer to Microsoft resources
for the latest information.

Chapter 1. eet your computer
This computer is equipped with an extensive selection of ports, providing convenient connectivity options for
multiple devices.
Front
1. Microphones* 2. Radar card*
3. ntegrated camera or nfrared ( R) camera* 4. ntegrated camera or nfrared ( R) camera shield*
5. R camera activity indicator* 6. Multi-touch screen*
© Copyright Lenovo 2024 1

7. Microphone mute/unmute indicator* 8. System status indicator
9. Microphone mute/unmute control 10. Monitor/computer mode switch
11. USB 3.2 connectors Gen 2 12. Headset connector
13. SD-card slot* 14. Power button
15. Optical drive activity indicator* 16. Optical drive eject button*
* for selected models
Statement on USB transfer rate
Depending on many factors such as the processing capability of the host and peripheral devices, file
attributes, and other factors related to system configuration and operating environments, the actual transfer
rate using the various USB connectors on this device will vary and will be slower than the data rate listed
below for each corresponding device.
USB device Data rate (Gbit/s)
3.2 Gen 1 5
3.2 Gen 2 10
3.2 Gen 2 × 2 20
Thunderbolt 3 40
Thunderbolt 4 40
System status indicator
Show the system status of your computer.
• Blinking for three times: The computer is initially connected to power.
• On: The computer is starting up or working.
• Off: The computer is off or in hibernation mode.
• Blinking rapidly: The computer is entering sleep or hibernation mode.
• Blinking slowly: The computer is in sleep mode.
Related topics
• “USB specifications” on page 6.
2M90a Gen 5 User Guide

Rear
1. Serial connector* 2. DisplayPort™ out connector
3. HDM ™ in 1.4/out 2.1 TMDS combo connector 4. Ethernet connector
5. USB-C® (3.2 Gen 2) connector 6. USB 3.2 connector Gen 1 (with smart power-on
feature)
7. USB 3.2 connectors Gen 1 8. Security-lock slot
9. Power cord connector 10. VESA® threaded holes (screws: M4 x 8 mm, 4 pcs)
* for selected models
Note: When mounting the computer on a VESA mount, position the computer monitor either horizontally
(with the screen facing forward and the side /O ports facing right) or vertically (with the screen facing forward
and the side /O ports facing down).
Serial connector
Connect an external modem, a serial printer, or other devices that use a serial connector.
HD I in 1.4/out 2.1 T DS combo connector
This connector will work after 10 seconds after connection as an HDM in or an HDM out connector,
depending on whether the connected device is a computer or a monitor.
Chapter 1.Meet your computer 3

Related topics
• “Lock the computer” on page 18.
• “Connect an external display” on page 14.
• “USB specifications” on page 6.
4M90a Gen 5 User Guide

Specifications
Specification Description
Dimensions
• Width: 539.6 mm(21.2 inches)
• Height: 352 mm (13.9 inches)
• Depth: 49.6 mm (2.0 inches)
Weight (without packaging) Maximum configuration as shipped: 8.1 kg (17.9 lb)
Hardware configuration Type Device Manager in the Windows search box and then press Enter. Type the
administrator password or provide confirmation, if prompted.
Power supply • 180-watt automatic voltage-sensing power supply
• 230-watt automatic voltage-sensing power supply
Electrical input • nput voltage: From 100 V ac to 240 V ac
• nput frequency: 50/60 Hz
Adaptability for power supply
• Mainland China: 220 V±22 V, 50 Hz±1 Hz
• Adaptive voltage positioning: 90 V to 264 V, 50/60 Hz
• With voltage selection switch: 90 V to 264 V, 50 Hz±1 Hz
emory
Double data rate 5 (DDR5) small outline dual in-line memory module (SOD MM)
Maximum memory capacity: 64 GB
Storage device
• M.2 solid-state drive*
To view the storage drive capacity of your computer, type Disk Management in the
Windows search box and then press Enter.
Note: The storage drive capacity indicated by the system is less than the nominal
capacity.
Video features
• Color display with White Light Emitting Diode (WLED) technology
• Color display with Full High Definition (FHD) technology
• Display size: 604.5 mm (23.8 inches)
• Display resolution: 1920 x 1080 pixels
• Multi-touch technology*
• The integrated graphics card supports the following:
– DisplayPort out connector
– HDM out connector
• The optional discrete graphics card provides an enhanced video experience
and extended capabilities.
Chapter 1.Meet your computer 5

Specification Description
Expansion
• Card reader*
• Memory slots
• M.2 solid-state drive slot
• Optical drive*
• Storage drive bay
Network features
• Bluetooth*
• Ethernet LAN
• Wireless LAN*
* for selected models
Operating environment
aximum altitude (without pressurization)
• Operating: From 0 m (0 ft) to 3048 m (10 000 ft)
• Storage: From 0 m (0 ft) to 12192 m (40 000 ft)
Temperature
• Operating: From 5°C (41°F) to 35°C (95°F)
• Storage:
– For common desktop computers: From -40°C (-40°F) to 60°C (140°F)
– For all-in-one desktop computers: From -20°C (-4°F) to 60°C (140°F)
Relative humidity
• Operating: 20%-80% (non-condensing)
• Storage: 10%-90% (non-condensing)
USB specifications
Note: Depending on the model, some USB connectors might not be available on your computer.
6M90a Gen 5 User Guide

Connector name Description
• USB-A 2.0 connector
• USB-A 3.2 Gen 1 connector
• USB-A 3.2 Gen 2 connector
Connect USB-A compatible devices, such as a USB-A
keyboard, USB-A mouse, USB-A storage device, or USB-
A printer.
• USB-C (3.2 Gen 1) connector
• USB-C (3.2 Gen 2) connector
• USB-C (Thunderbolt 3) connector
• USB-C (Thunderbolt 4) connector
• Charge USB-C compatible devices with the output
voltage and current of 5 V and 3 A.
• Connect to USB-C accessories to help expand your
computer functionality. To purchase USB-C
accessories, go to https://www.lenovo.com/accessories.
The Vantage app
The Vantage app is a customized one-stop solution to help you maintain your computer with automated
updates and fixes, configure hardware settings, and get personalized support.
To access the Vantage app, type Vantage in the Windows search box.
Notes:
• The available features vary depending on the computer model.
• The Vantage app makes periodic updates of the features to keep improving your experience with your
computer. The description of features might be different from that on your actual user interface. You can
download the latest version of Vantage app from Microsoft Store.
The Vantage app enables you to:
• Know the device status easily and customize device settings.
• Download and install UEF B OS, firmware, and driver to keep your computer up-to-date.
• Monitor your computer health, and secure your computer against outside threats.
• Scan your computer hardware and diagnose hardware problems.
• Look up warranty status (online).
Chapter 1.Meet your computer 7

• Access User Guide and helpful articles.
8M90a Gen 5 User Guide

Chapter 2. Get started with your computer
Access networks
This section helps you connect to a wireless or wired network.
Connect to Wi-Fi networks
Click the network icon on the bottom right of your display to connect to an available network. Provide
required information, if needed.
Note: The wireless LAN module on your computer may support different standards. For some countries or
regions, use of 802.11ax may be disabled according to local regulations.
Connect to the wired Ethernet
Connect your computer to a local network through the Ethernet connector on your computer with an
Ethernet cable.
© Copyright Lenovo 2024 9

Adjust the computer stand (for selected models)
For full-function monitor stand
For tilt-only stand
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For UltraFlex V Stand
Rotate the monitor (for selected models)
The full function stand supports rotating the computer monitor from horizontal to vertical in certain usage
scenario. Before rotating, you must adjust the monitor to the highest point (110 mm) and the tilt angle to
maximum (backward 20 degrees).
Adjust the desktop settings
Before rotating the computer monitor direction, you might need to adjust the desktop direction accordingly
for better use experience. The preinstalled ntel Graphics Command Center app ( GCC) helps you enable and
customize system hotkeys so that you can use shortcuts to personalize your desktop settings. To download
the latest version of GCC, go to https://www.microsoft.com/store/product d/9PLFNLNT3G5G.
1. To access the GCC app, type Intel Graphics Command Center in the Windows search box.
2. Accept the license of GCC.
3. Turn on the Enable System Hotkeys switch. Customize the landscape and Portrait hotkeys according
to your preference.
4. Press Ctrl + Alt + Left ( by default) to change the desktop from horizontal to vertical.
5. Press Ctrl + Alt + Up (by default) to change the desktop from vertical to horizontal.
Rotate the monitor
Rotate the computer monitor clockwise from horizontal to vertical. You also can rotate the monitor
counterclockwise from vertical to horizontal when needed.
Chapter 2.Get started with your computer 11

Adjust the tiltable camera (for selected models)
You can adjust the camera angle by tilting the camera forward or backward for better usage experience.
Use the touch screen (for selected models)
f your computer display supports the multi-touch function, you can navigate the screen with simple touch
gestures. For more touch gestures, refer to https://support.microsoft.com/windows.
Note: Some gestures might not be applicable when you use certain apps.
Illustrations and description Illustrations and description
Tap once to single click Tap twice quickly to double-click
12 M90a Gen 5 User Guide

Illustrations and description Illustrations and description
Tap and hold to right-click Slide to scroll through items
Zoom in Zoom out
Swipe from the left: view all open windows (Windows 10)
Swipe from the left: open widget panel (Windows 11)
Swipe from the right: open action center (Windows 10)
Swipe from the right: open notification center (Windows
11)
Swipe downwards shortly: show title bar
Swipe downwards: close the current app
Drag
aintenance tips
• Turn off the computer before cleaning the touch screen.
• Use a dry, soft, and lint-free cloth or a piece of absorbent cotton to remove fingerprints or dust from the
touch screen. Do not apply solvents to the cloth.
• The touch screen is a glass panel covered with a plastic film. Do not apply pressure or place any metallic
object on the screen, which might damage the touch panel or cause it to malfunction.
Chapter 2.Get started with your computer 13

• Do not use fingernails, gloved fingers, or inanimate objects for input on the screen.
• Regularly calibrate the accuracy of the finger input to avoid a discrepancy.
Connect an external display
Connect a projector or a monitor to your computer to give presentations or expand your workspace.
Connect a wireless display
Ensure that both your computer and the wireless display support Miracast®.
Press Windows logo key + K and then select a wireless display to connect.
Change display settings
1. Right-click a blank area on the desktop and select display settings.
2. Select the display that you want to configure and change display settings of your preference.
Transfer data
You can install a disc or media card to transfer data.
Use the optical drive (for selected models)
f your computer has an optical drive, read the following information.
Know the type of your optical drive
1. Type Device Manager in the Windows search box and then press Enter. Type the administrator password
or provide confirmation, if prompted.
2. Select an optical drive, and then follow the on-screen instructions.
Install or remove a disc
1. With the computer on, press the eject button on the optical drive. The tray slides out of the drive.
2. nsert a disc into the tray or remove a disc from the tray, and then push the tray back into the drive.
Note: f the tray does not slide out of the drive when you press the eject button, turn off the computer. Then,
insert a straightened paper clip into the emergency-eject hole adjacent to the eject button. Use the
emergency eject only in an emergency.
Record a disc
1. nsert a recordable disc into the optical drive that supports recording.
2. Do one of the following:
• Type AutoPlay in the Windows search box and then press Enter. Turn on Use AutoPlay for all media
and devices.
• Open Windows Media Player.
• Double-click the SO file.
3. Follow the on-screen instructions.
Use a media card (for selected models)
f your computer has a SD-card slot, read the following information.
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Install a media card
1. Locate the SD-card slot.
2. Ensure that the metal contacts on the card are facing the ones in the SD-card slot. nsert the card firmly
into the SD-card slot until it is secured in place.
Remove a media card
Attention: Before removing the card:
1. Click the triangular icon in the Windows notification area to show hidden icons. Right-click the icon
prompting you to safely remove hardware and eject media.
2. Select the corresponding item to eject the card from the Windows operating system.
3. Press the card and remove it from your computer. Store the card safely for future use.
Privacy (for selected models)
Privacy protection
When peeping behavior is detected, it triggers an alert message to display within seconds and blurs your
computer screen to protect your privacy.
Notes:
• f the privacy protection feature is enabled, screen blurring is enabled by default while an alert message
needs to be further enabled. You can customize the warning interval based on your preference.
• For Windows 10 operating system, the privacy protection is enabled automatically after the startup of the
operating system. For Windows 11 operating system, the privacy protection is enabled automatically 1
hour the startup of the operating system.
Human presence detection
The radar card detects user presence. This feature awakens your computer when you are facing the screen.
And when you leave, it automatically locks the computer according to the screen-off timer settings, which
can be customized. The default screen-off timer is 10 seconds.
Note: Ensure that you have enabled the human presence detection feature and registered your face
identification. Lenovo does not collect any personal data.
Chapter 2.Get started with your computer 15

Connect to a Bluetooth device
You can connect all types of Bluetooth-enabled devices to your computer, such as a keyboard, a mouse, a
smartphone, or speakers. To ensure successful connection, place the devices at most 10 meters (33 feet)
from the computer.
Conventional pair
This topic helps you connect to a Bluetooth device by conventional pair.
Step 1. Type Bluetooth in the Windows search box and then press Enter.
Step 2. Turn on both the Bluetooth on your computer and the Bluetooth device. Make sure the device is
discoverable.
Step 3. Select the device when it is displayed on the Add a device list, and then follow the on-screen
instructions.
Notes: f the Bluetooth connection failed, do the following:
1. Type Device Manager in the Windows search box and then press Enter.
2. Locate the Bluetooth adapter. Right-click and select Update driver.
3. Select Search automatically for drivers, and then follow the on-screen instructions.
Swift pair
This topic helps you connect to a Bluetooth device by swift pair.
f your Bluetooth device supports swift pair, do the following:
Step 1. Enable swift pair notification on Bluetooth settings page.
Step 2. Turn on both the Bluetooth on your computer and the Bluetooth device. Make sure the device is
discoverable.
Step 3. Click Connect when a swift pair notification appears on your computer.
Notes: f the Bluetooth connection failed, do the following:
1. Type Device Manager in the Windows search box and then press Enter.
2. Locate the Bluetooth adapter. Right-click and select Update driver.
3. Select Search automatically for drivers, and then follow the on-screen instructions.
ICE performance mode
The CE performance mode helps you adjust the acoustic and thermal performance of your computer. Three
options are available:
16 M90a Gen 5 User Guide