The following notes relate to identifying, configuring, and using an IBM PC 5150. This system was the original home/office PC offered by IBM in August 1981.
For an even older system, see my IBM 5110 notes here or IBM 5100 notes here.

The following notes describe various useful things to do with this system, plus a few “quality of life” upgrades using some modernized components.
Much has already been written on what the 5150 system is, why it is significant, and how it came about. Here are a few references to existing discussions on those topics…
- DOCUMENTARY: Why and How IBM ended up creating the PC (and ended up choosing the 8088 CPU) – YouTube
- https://tvtropes.org/pmwiki/pmwiki.php/UsefulNotes/IBMPersonalComputer
- https://www.bcs.org/articles-opinion-and-research/how-the-pc-was-born-and-why-it-hasnt-died-yet/
- https://www.os2museum.com/wp/the-ibm-pc-41-years-ago/
- My own: Overview of IBM PC History (1980 – 2020).
My focus below is on specific aspects of the IBM PC 5150, as a guide to help those who may find such a system but might not be familiar with what it can do or how to use it.
TABLE OF CONTENTS
- Things an IBM PC 5150 Can Be Used For (in the 21st century)
- Determining a “Model A” vs “Model B” IBM PC 5150 (sample BASIC to count memory)
- Motherboard Dip Switch Settings (set memory size and disk drive count)
- Connecting a Keyboard (options for Model F vs Model M)
- Setting up MDA/CGA (adapting to modern display)
- Setting up EGA/VGA
- Setting up a Tape Deck Connection (because the 5150 can)
- Setting up Floppy Disk Controller (and external connection 4x drives)
- Setting up HxC2001 Floppy Disk Emulator
- Setting up XT-IDE (add simulated hard drive using CompactFlash)
- Setting up WiModem232 (about serial IO and setup a modem to talk to BBSs)
- Setting up NIC (Network Interface Card and mTCP)
- Setting up DOS (PC-DOS, MS-DOS, DR-DOS and DESQView)
- Setting up SoundBlaster (and using MODM and GLX)
- Setting up Joystick
- Setting up Serial Mouse
- About the Author
My Quick System Overview
A “stock” (unmodified) IBM PC 5150 built and sold in 1983 (for CPU, power supply, main board, case and dual disk drives).
CATEGORY | DESCRIPTION | VINTAGE |
CPU | 4.77 MHz Intel 8088 (stock) with stock ’82 BIOS | 1983 |
SLOT 1: Hard Drive and RAM | XT-IDE (with 128MB CF, with 1MB RAM extension) | 2016 |
SLOT 2: Audio | Sound Blaster 2.0 CT1350B (15-pin Joystick Port) | 1991 |
SLOT 3: Network Interface | 3COM Etherlink III 3C509B-TP (RJ45 ethernet) | 1999 |
SLOT 4: Display | CGA/MDA (IBM OEM) | 1983 |
SLOT 5: Serial + Parallel Adapter | IBM OEM | 1984 |
OS | DR-DOS 3.41 (can boot 256KB RAM, supports 128MB HDD) | 1989 |
Mouse Driver | Microsoft Mouse 8.20 | 1992 |
OPTIONAL H/W | 8-bit ISA OTIVGA (Oak Technology) | 1988 |
OPTIONAL H/W | WiModem232 (serial modem) | 2016 |
Some have asked about the disk drive cover. This was not an IBM part. These covers were obtained via the following advertisement in PC Magazine:

REFERENCES
The following sites contain what I consider to be reliable and interesting sources of information related to the IBM PC.
IBM PC Technical Source Archive: http://www.minuszerodegrees.net
Vintage Computing Forum: https://www.vcfed.org/forum/forum
Al’s Hot Rod XT: https://www.youtube.com/watch?v=moKVor7HE-A (including mTCP overview and setup)
PC Corner: https://www.pcorner.com/
WinWorld: https://winworldpc.com/home
Don Barber creating boot disk using serial IO: Floppy-only PC with only blank floppies? No problem. | by Don Barber | Medium