M321

The PCChips M321 (rev. 2.x), manufactured by Hsing Tech (commonly branded as PCChips), is a 386DX motherboard released in 1992. Designed around the Intel 386DX processor, it was aimed squarely at cost-conscious users looking for an affordable upgrade path in the early '90s.

Despite its low price tag, the M321 offered a decent feature set for the time:

• It came with a PGA132 socket supporting Intel 386DX CPUs and optional 80387DX or Weitek 3167 math coprocessors.

• It supported up to 32MB of RAM via 8x 30-pin SIMM slots.

• The cache could be configured from 32KB to 256KB, although some models shipped with fake or non-functional cache — a common issue with some PCChips boards.

The motherboard was built using a relabeled Opti 82C391 chipset, which provided basic memory and I/O functionality. It also included onboard I/O for floppy, IDE, serial, and parallel ports, which was convenient for reducing the need for expansion cards.

In terms of compatibility, it performed well with:

• MS-DOS 6.22

• Windows 3.1 / 3.11

• IBM OS/2 1.x/2.x

• And even early Linux distros like Slackware, if you kept things lightweight.

Performance-wise, it wasn’t a powerhouse, but for typical DOS productivity, education software, or early PC games, it was serviceable. The Baby AT form factor made it a good fit for smaller cases, and its minimal power requirements allowed it to run on modest power supplies.

However, the board was not without controversy. PCChips became infamous for rebranding chipsets and sometimes even including fake chips or misleading specs. Many M321 units were sold with mislabeled components or unusable cache chips soldered on purely for marketing appeal.

Still, the M321 stands today as a nostalgic piece of retro computing history — a reminder of the budget boom in personal PCs and how far DIY computing has come since.