NM-B421 – Lenovo ThinkPad E480
The Lenovo ThinkPad E480, Lenovo ThinkPad E580 and Lenovo ThinkPad R480 are built on the NM-B421 board designed by LCFC. The catalog lists 15 files for it: 11 BIOS files, 2 schematics, 3 boardviews and 2 EC firmware images.
Revisions seen in file names: 1.0. The BIOS dumps are 16 MB images. ODM project names: EE480 and EE580. The earliest file dates from August 2020 (BIOS Archive, Schematics & Boardviews Archive and Cyberlan Electronics).
BIOS dumps 11
Schematics 2
Boardviews 2
Board facts
| Board number | NM-B421 |
|---|---|
| Designed by | LCFC |
| Platform group | NM-B |
| ODM project | EE480, EE580 |
| Revisions | 1.0 |
| BIOS chip size | 16 MB |
| CPU generation | Intel 7th gen, Intel 8th gen |
| First seen | 2020-08-31 |
| Source channels | BIOS Archive, Schematics & Boardviews Archive, Cyberlan Electronics, Boardview Schematics |
| About the number | LCFC is Lenovo's joint venture with Compal; its main boards use NM- numbers and sub-boards NS- numbers. |
Laptops that use NM-B421
- Lenovo ThinkPad E480
- Lenovo ThinkPad E580
- Lenovo ThinkPad R480
What these files are for
A BIOS dump is a full image of the board's SPI flash chip. It is written back with an SPI programmer when the original firmware is corrupted, after a chip replacement, or to recover from a failed update. Read and save the original chip first: serial number, DMI data and the Intel ME / AMD PSP state differ between boards.
A schematic is the circuit diagram of the main board: power rails, power-up sequence, component values and net names. It is the reference for measuring voltages and tracing a fault.
A boardview is the component placement map of the PCB: click a part or a net and the viewer highlights where it is and what it connects to. Used together with the schematic to find test points.
Tools to open these files
| Format | What it is | Open with |
|---|---|---|
| .bdv | Honhan .bdv boardview | OpenBoardView, FlexBV or Honhan BoardViewer |
| PDF schematic | any PDF reader; Sumatra PDF and Foxit handle large schematics well | |
| .rar | RAR archive | 7-Zip or WinRAR |
| .tvw | Tebo-ICT .tvw boardview | FlexBV or Tebo-ICT View |
| .zip | ZIP archive | 7-Zip, WinRAR or the built-in Windows extractor |
| .bin | BIOS image inside the archive (usually .bin) | a CH341A, XGecu T48 / TL866II Plus or RT809H programmer |
Questions
Are these files free?
2 of the posts are marked VIP or paid in their source channel; the others are ordinary posts. ChambersDesignInc.com does not host or sell files.
What BIOS chip size does NM-B421 use?
The BIOS images for NM-B421 are 16 MB.
Who designed the NM-B421 board?
NM-B421 is an LCFC board number used by Lenovo.
Which laptops use the NM-B421 board?
Files in the catalog link NM-B421 to the Lenovo ThinkPad E480, Lenovo ThinkPad E580 and Lenovo ThinkPad R480.
Is there a boardview for NM-B421?
Yes, 3 boardview files in .bdv and .tvw format.
Where do the download links go?
Each button opens the original public Telegram post the file was shared in. ChambersDesignInc.com only indexes and cross-references those posts.