Sharp PC-4521 Internal View

Nix McRetro // 8th October 2012 // IBM PC, Repairs, YouTube

Here’s something a little different: a Sharp PC-4521 from the PC-4500 portable-computer family.

This one isn’t mine. I just managed to have a poke around inside it while the owner was absent.

The PC-4521 was the hard-drive-equipped version of the series. It uses an 80188-compatible NEC V40 running at 7.16 MHz, has 640 KB of RAM, a 720 KB 3.5-inch floppy drive and a 20 MB hard drive.

The display is a backlit monochrome LCD running at 640 x 200 pixels.

That explains the wonderfully strange proportions of the screen.

Sadly, this machine’s hard drive was already dead and the floppy drive seemed to be on its way out as well.

Still, the hardware inside is worth documenting, and that long, wide display is fantastic.

What an aspect ratio!

Sources

IT History Society - Sharp PC-4500 - secondary historical reference for the PC-4500 family specifications, including CPU, memory, display and storage.

AI-assisted revision: This post was reviewed and edited with OpenAI GPT-5.6 Sol on 29 September 2026 for fact-checking, sourcing, and editorial cleanup. Final editorial responsibility remains with the author.