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IBM PC 5150

The System

IBM PC 5150 in mint condition
16k-64k motherboard with v2 BIOS - P/N 184041XM413 - S/N 0216354
Dual full height 320k floppy drives
IBM floppy controller - P/N 1809121 XM 42
IBM MDA and parallel port - P/N 1804057 362XM
IBM power supply - P/N 1800841
Everex EV-138 memory card with 576K (maxed)
IBM 5151 monitor
Model F Keyboard
Original purchase invoice from 1982!
IBM DOS 3.3

Log

*20110223** Purchased from Vintage Computer Marketplace from the original owner. I learned after bidding that if it hadn't sold, it was destined for the big electronics grinder in the sky. So sad!

Vintage Computer Marketplace (seems to be defunct)

*20150829**

Disassembled, cleaned, and reassembled everything. Both floppy drives work. Motherboard has the

v2 BIOS, which does not support hard drives, and does not sense switch 5 of SW2 which limits it to 544KB of RAM. Cleaned latex paint off power cords etc with rubbing alcohol. Cleaned floppy drives.

Glued monitor case cracks with E6000. The back shell of the monitor is somewhat brittle but this

stabilized it.

Replacement cork pads from Lorne on Vintage Computer Marketplace. Besides the monitor cracks, everything seems to function correctly.

Switches

http://www.minuszerodegrees.net/5150/misc/5150_motherboard_switch_settings.htm

SW1 01000001

http://www.minuszerodegrees.net/5150/ram/5150_ram_16_64_SW2.jpg

SW2 00000000

TODO

Upgrade BIOS to the 10/27/82 version. This will allow full 640K RAM support, and adds support for expansion ROMs, so the XT-IDE card will be recognized. The original EPROM in this machine is a 36887 made by Mostek, and the EMP-20 apparently does not support this (it's not listed, and configuring as a Motorola 68766 and then reading does not work.) Search for EPROM MCM68766. These are commonly sold with the '82 BIOS pre-burned (most common use case for this old EPROM?) or I can burn my own.
8087
Find IBM DOS 1.1 (only thing from original invoice that I am missing)
NEC V20. Not original but still from the time period.
XT-IDE

BIOS

My machine has the v2 BIOS. This BIOS only recognizes up to 544KB RAM, and does not support hard drives.

References

IBM 51xx PC Family Computers

Description at old-computers.com