Compaq Portable III upgrades

Compaq's 12 MHz 80286 portable PC, offered with an optional two-slot 8/16-bit expansion unit.

Also called: Compaq Portable III Personal Computer, Portable III

At a glance

Introduced: 1987

Products listed: 1

Exact-model evidence: 1

Family/interface evidence: 0

Upgrade types: 1

Vintage searches: 0

Upgrade directory: Portable III

Browse everything below, or filter by product type, availability, and compatibility basis. Notes explain whether evidence names an exact target, a broader family, or only the relevant bus or interface for this computer.

Showing 1 product.

Status Product What it does Links

Status	Product	What it does	Links
Build itChecked Jul 25, 2026	Compaq Portable III Battery Moduleby Sergey Kiselev battery replacement module open hardware diy	Open replacement battery module for the Compaq Portable III using a CR2477N coin cell. For this system (exact model): The repository is specifically for the Compaq Portable III. Verify coin-cell polarity and header orientation before connecting the completed module. This is a self-assembly project rather than a retail product. Follow the documented cell polarity and solder the pin headers in the specified upside-down orientation. Sources Compaq Portable III Battery Module repository	Battery module project

Build itChecked Jul 25, 2026

Compaq Portable III Battery Moduleby Sergey Kiselev

Open replacement battery module for the Compaq Portable III using a CR2477N coin cell.

For this system (exact model): The repository is specifically for the Compaq Portable III. Verify coin-cell polarity and header orientation before connecting the completed module.

This is a self-assembly project rather than a retail product. Follow the documented cell polarity and solder the pin headers in the specified upside-down orientation.

Sources

Compaq Portable III Battery Module repository

Battery module project