Brand: Lenovo

Type: Motherboard / System Board / Mainboard

MPN / FRU: 5B21N89351

Processor: Intel Core Ultra 7 165U

Processor Family: Intel Core Ultra 7

CPU Cores / Threads: 12 Cores / 14 Threads

Memory: 64GB Onboard / Soldered RAM

Graphics: Integrated Intel Graphics

Compatible Brand: Lenovo

Compatible Product Line: Lenovo ThinkPad X1

Compatible Models: ThinkPad X1 Carbon Gen 12 / ThinkPad X1 2-in-1 Gen 9

Machine Types: 21KC, 21KD, 21KE, 21KF

Form Factor: Genuine Lenovo OEM Laptop System Board

Country/Region of Manufacture: China

Condition: New

Manufacturer / Reference Numbers

5B21N89351 — Primary FRU / MPN

5B21R86322

5B21S34849

5B21U27772

5B21T63653

Product Description

Upgrade or repair your premium Lenovo ThinkPad with this NEW Genuine Lenovo OEM System Board, FRU 5B21N89351, featuring the powerful Intel Core Ultra 7 165U processor and 64GB of onboard memory.

This is not a generic aftermarket replacement. It is a genuine Lenovo system board designed for supported configurations of the ThinkPad X1 Carbon Gen 12 and ThinkPad X1 2-in-1 Gen 9 platforms.

The Core Ultra 7 165U platform provides a modern high-performance architecture designed for premium business-class ThinkPad systems, while the integrated 64GB memory configuration makes this an excellent replacement board for high-end X1 configurations.

Key Features

Genuine Lenovo OEM motherboard

FRU / MPN: 5B21N89351

Intel Core Ultra 7 165U processor

12-core / 14-thread CPU architecture

64GB onboard system memory

Integrated Intel Graphics

Designed for premium Lenovo ThinkPad X1 systems

Ideal for motherboard failure, liquid-damage repair, board-level failure, or high-spec replacement

Professional-grade replacement part

New condition

Compatibility

Designed for compatible configurations of:

Lenovo ThinkPad X1 Carbon Gen 12

Machine Type 21KC

Machine Type 21KD

Lenovo ThinkPad X1 2-in-1 Gen 9

Machine Type 21KE

Machine Type 21KF

IMPORTANT COMPATIBILITY NOTICE

Lenovo may use multiple system-board FRUs within the same laptop model depending on processor, memory, WWAN, regional configuration, BIOS configuration, and other factory options.

Please match FRU 5B21N89351 with your existing motherboard or verify compatibility using your Lenovo machine type / serial number before purchase.

Do not purchase based only on the laptop's exterior model name.

What You Will Receive

1 × Genuine Lenovo System Board / Motherboard — FRU 5B21N89351

Intel Core Ultra 7 165U processor and 64GB onboard memory are integrated into the system board.

Only items specifically shown or described as included are included.

SSD, heatsink/fan, battery, display, keyboard, charger, wireless cards, and other laptop components are not included unless specifically pictured and stated otherwise.

Why Buy This Board?

This is a very high-spec replacement motherboard for Lenovo's premium ThinkPad X1 platform.

Instead of replacing an entire X1 Carbon or X1 2-in-1 because of motherboard failure, this board can restore the machine while retaining a powerful configuration featuring:

Intel Core Ultra 7 + 64GB RAM

Perfect for:

Professional laptop repair

IT departments

Lenovo service technicians

Corporate ThinkPad refurbishment

High-end workstation replacement

Electronics repair businesses

Shipping

US SELLER

Carefully packed using appropriate anti-static protection and protective packaging.

Fast shipping from the United States.

Tracking will be provided with shipment.

Because this is a high-value electronic component, serial numbers and identifying markings may be documented prior to shipment.

Buyer Responsibility

Motherboard replacement requires proper technical knowledge and ESD-safe installation procedures.

Please verify the FRU and system compatibility before installation.

Damage caused by incorrect installation, improper handling, static discharge, incorrect firmware procedures, or incompatible components is not considered a product defect.