DolchPAC 65

DolchPAC Videos Playlist

In an ocean of mediocre and forgettable 1990's consumer PCs, the sturdy, all-in-one luggable DolchPAC stands out as a nice piece of engineering.

I needed an old PC to serve as a bridge between the pre-PC computers I restore and the moderns ones I work with. It needed to support old interface cards with many ISA and PCI slots, 5.25" floppies, be able to run old DOS utilities and drivers, but modern enough to boot in WinXP and Linux and communicate easily with its modern brethren. I also wanted a portable and all in one design to serve as bench instrument. And well engineered: the poorly slapped together 1990's PC plastic boxes, which are just buggy piles of obsolete generic components, have no place in my collection.

Impossible? No! The Dolch PAC 65 fits the bill, and more. Pentium II based, having one ISA and 4 PCI slots, an integrated LCD screen, a superb and highly collectible keyboard with a trackpoint mouse. On top of that it was made by my late friend and Silicon Valley entrepreneur Volker Dolch.

This playlist covers everything from repairing the hardware to installing no less than 5 operating systems (DOS, WinNT, Win98, WinXP and Linux).

The DolchPACs appear in my videos connected to all kind of HP equipment via HP-IB, 9-track tapes via SCSI, able to read and write oddly formatted 5-1/4" Floppies under DOS, or talking to my old Data IO PROM burner or my 600 line per minute line printer via its two serial ports. All while being modern and accessible citizens on the network while running Win98, XP or Linux.

In Dolch we trust!

My late friend Volker Dolch with his wife Mai

DOS 7.10 Installation

One of the main points of my Dolch is having the ability to run utilities that only work in pure DOS. I use the latest DOS version that comes with Windows 98. It allows me to run pure DOS when I need to, then switch back and forth to a much more efficient GUI and network-friendly environment when I am done. Then back to DOS with the Windows 98 Exit to DOS shortcut.

Besides what's provided by Win98, my custom DOS installation, including all of my favorite software and the DOS drivers, lives in the folder C:/DOS. The drivers themselves are in C:/DOS/DOS. The setup is completed by an AUTOEXEC.BAT and a CONFIG.SYS at root level. The complete installation files are provided below. Just keep the same structure and drop the files in your Win98 C: drive and that should work.

The installation below has the following programs:

  • Two basic programs, QBasic and QB45
  • DataIO's PL.EXE software for my vintage Data I/O 29B PROM programmer
  • HP disk utilities: HPDIR and HPDRIVE HP-IB disk emulators by Ansgar Kueckes, and HP LIF utility
  • ImageDisk (IMD) universal format floppy diskette read, write and archive utility
  • OMNIDISK, the super low level floppy utility. Harder to use, but it will read anything: sector, bytes, formatting info etc...
  • KERMIT, the user friendly terminal emulator (and file transfer tool, but I mostly use it to transform my Dolch into a serial dumb terminal emulation)
  • NDTERM, the technical terminal emulation with more special character display options
  • Overland DEPOT2 and DEPOT4 9-track tape tools
  • scsi2tap: utility to dump a SCSI 9-track tape to a SIMH tape file by Chuck Guzis
  • tap2scsi: utility to read and write from SCSI 9-track tape drives to SIMH tape files (better than scsi2tap), by John Wilson, with source code
  • XTREE: the iconic "GUI for DOS" program

The following drivers and batch files are included in the /DOS/DOS folder:

  • CDROM
  • Mouse
  • SCSI
  • READNTFS to allow DOS to read NTFS volumes
  • Batch files to launch configured kermit (TERM) or ndterm (TERM2) terminals easily from the command line

The trickiest part of the DOS installation is the drivers for the cards. Refer to the first video for how this is done. At the end of the second video you see a boot into pure DOS followed by switch to the full Win98 GUI.


Windows 98 Installation

You'll find the files I used in my Windows 98 installation below

  • Acrobat 5, the last one that works in Win98
  • HP TCP-IP port installer, allows to use an Ethernet network printer
  • ie 5.5. sp2, the only Microsoft browser that works on Win98. Actually it does not work, really
  • K-Meleon 1.5.4, the last K-Meleon that works on the Pentium II. A modern browser that works very well.
  • PQMagic, the formatter I use
  • Drivers for the SCSI, HPIB, On-board Ethernet, USB and Soundblaster card I use in the video
  • Unofficial Win98 SP3, gives you modern networking
  • USB Drivers for Win98SE, gives you USB2.

Video of the Windows 98 Installation. There are a lot of quirks.

Windows XP Installation

You'll find the files I used in my Windows XP installation below

  • Web browsers that will work on the Pentium II. Not-quite-functional Explorer 8 is there for reference, and because Windows really requires it, but I use K-Meleon and SeaMonkey relatively modern browsers.
  • Windows Update Fix, if you ever get stuck with your machine spending all its time trying to update
  • Drivers, in particular the Trident Video (necessary) and the Creative Soundblaster drivers. GPIB drivers are for HPDRIVE and HPDIR.
  • New Trident Video driver has been added. It is free of the glitch of the previous driver. It is the one that came with the machine on Windows NT, and a viewer modified the .inf file so XP can install it too (thank you Jacques G.!)

This is the Windows XP installation videos. There are a few quirks.

Linux Installation

The Crunchbang installation CD I used is available below. Follow the video for the many Debian-fu commands necessary. The crucial Xorg.conf file that allows the use of the high resolution screen is included also.

This is the LInux installation is in the second part of the video. A good amount of Debian-Fu is needed, particularly to configure the keyboard and the display, but its all explained.

AWARD BIOS information

It turns out that my board fault was a bad BIOS. The BIOS was made by Award, and flashed into a Winbond W29C020P flash memory chip. The chip was apparently fine, but when accidentally reversing the internal connector to the internal IDE drive (there is no proper keying on the special Dolch adapter board!), a small sector of the flash BIOS apparently gets corrupted during boot up. A simple reflash was all it needed. Finding the correct BIOS image to reflash it was more difficult. I could not get it from Advantech. I instead dumped the image of the BIOS in one of my other DolchPACs, and also got one version of the web that worked equally well. Both versions are included below, as well as the datasheet of the Windbond flash chip.

The BIOS reflashing process is covered in this video. I used a TL866A PROM programmer, about which I have only good things to say. A commenter noted that if you have another good board with a good BIOS, you can use the Uniflash utility to dump an image or reflash your bad BIOS.

Advantech CI6BM Motherboard Information

In the first episode of my 3rd DolchPAC restoration, I run into a major snag and my board refuses to even boot BIOS and go into POST. This did force me to look into detail at the power supply, motherboard, it's processor, on-board power regulating compoments, clock chip, monitor chip and eventually its BIOS, which was the root cause of the fault.


The motherboard is an Advantech CI6BM. It is a Taiwanese made board, clearly targeted at the industrial embedded computer market, complete with PC 104 connectors (unused in the Dolch). Vintage replacement boards are still available but command very high prices on eBay, probably because it is found inside various industrial equipment that people need to keep running. The document below is the only manual I found about that board. Advantech told me they were actually the distributor, as the board was engineered by a now defunct Taiwanese company called "My Computer". Go try to search something under that name...

Motherboard ci6bm10d Pentium II (Advantech, Dolch, My Computer).pdf

The basics of the board are summarized in the table below. They are Pentium II based boards, with a 440BX chipset, Trident 9520 video chip, PC100 memory, and include a Windbond 83977 hardware monitor chip.

Pentium II Information

There are relatively few public technical documents about the Pentium II and the Slot 1 pinout, here is what I found:

The Pentium II is a cost reduced version of the previous ceramic multichip package Pentium Pro, and in a rather odd format. The processor chip sits on its own ballgrid organic carrier which in turn sits on a larger board that hosts the cache memory, which is not made by Intel. There are different versions of the processors boards with more or less cache memory and few different generations of processor chips, which got progressively faster and got more cache.

Pentium II, Deschutes 333MHz version

Pentium II, Klamath

Pentium II, 400 Mhz

The whole thing is then packaged in a large cartridge, usually paired with an integrated heatsink on the back which directly touches the backside of the processor chip. A few pictures of the processors below. It had a rather pretty hologram picture of the chip stuck on the package, which more than made up for the disappointing appearance of the cost conscious engineering inside. The cartridge then slides into a board-edge connector assembly known as the "Slot 1".

Dolch motherboard with the processor removed showing the "Slot 1" connector in which the Pentium II cartridge slides.

Board Components Datasheets

During my extensive debug, I checked the power mosfets, clock chip, memory, hardware monitor chip and BIOS chips I found on the board. Here are the datasheets I gathered.

LCD Screen Information

There are different types of screens in Dolch PAC65s. Two of my Dolches have a 800x600 TFT screen. Both of these had bad illumination, which turns out to be from broken plastic diffusers which developed cracks, and not the fluorescent illumination tubes as I first thought. Any how, I had to change them. They were:

Brand: Goldstar, Philips or LG
Model:LP 121S2
P/N: 6870L-0046A

My third Dolch has a 1024x768 screen which I did not have to change, so I did not look what part number it is.

Both of these resolutions can be driven by the on-board graphics chip, you just change the jumpers as per motherboard instructions

Below is a picture of the 800x600 LG TFT screen.