PC 20-III

Serial: 314815

• mainboard revision: 6.2A
• CPU: Siemens 8088-1 running at 4.77MHz (Standard), 7.16Mhz (Turbo), or 9.54MHz (Double)
• Optional 8087 math co-processor
• RAM: 640KB
• ROM: 32KB Phoenix self-configuring BIOS Version 4.41
• Chipset: Faraday FE2010A single chip controller IC
• Clock: Battery-backed Real Time Clock (RTC) maintains the date and time while the system is powered off
• Floppy drives (SMC FDC9268 controller):
  • A: 720K 3.5″ Chinon FB-354
  • B: 360K 5.25″ Chinon FZ-502
• Hard Drive: Western Digital 20MB WD 93028-X [XTA]
• Sound: On-board piezoelectric beeper
• Ports:
  • 9-pin d-sub bus mouse port compatible with Commodore Amiga 1352 mouse (MOS 5720)
  • 25-pin d-sub RS-232 serial port (Western Digital WD8250-PL)
  • 25-pin d-sub 8-bit Centronics parallel port (Paradise PPC1)
  • DIN-5 IBM PC XT-compatible keyboard port
  • 9-pin d-sub RGBI/Monochrome video port
  • RCA composite video port
• Video: Onboard Paradise PVC4
  • MDA Monochrome Text
  • Hercules Monochrome Graphics
  • CGA Color Text and Graphics
  • Plantronics Colorplus Graphics
  • Alpha132 Monochrome Text
• 3x 8-bit ISA slots for expansion
• 75 watt power supply

• work performed:
  • battery removed, minimal leakage, all neutralized and cleaned
  • FDDs disassembled, cleaned and lubricated
  • whole machine completely dismantled and cleaned
  • mainboard and PSU recapped with Rubycon brand 105° type
  • HDD revived [bearings oiled/tefloned]
  • HDD backup [Ghost 2]

• notes:
  • floppy metal cover from #250010
  • A:\ not working correctly