Autie retro tech geek!

90s RetroComputing using Industrial PCs

This page is primarily about my 90s PC “tiny industrial builds”.  For my 80s collection, go HERE.

Remember the good ‘ol days of C:\>, SET BLASTER, Cubic Player, and the PCDOS DemoScene? The glory days of computing when you set your modem’s jumpers to COM1, IRQ4 and it always worked? Or when you made your mouse work simply by typing MOUSE.COM and your CDROM worked only when you loaded MSCDEX.EXE? How about that trusty SoundBlaster which required no drivers and always worked on A220 I5 D1? The days of DIR, DEBUG and loading VBE drivers for your VGA card are long gone…or are they?

Those were the days I first got started with computers, and I was always at the command prompt, despite having Windows 3.1 floating around. I have a deep love for DOS, much like some LINUX folk do for their OS.

These machines were built for the main purposes of faithfully playing retro music such as OPL3 tunes, XG MIDI, MOD/S3M/IT/XM tracker modules, oldskool demos and DOS games.  Because they’re based around industrial Single Board Computers (SBC), I can very easily switch CPUs; I have 486 and Pentium SBCs to choose from as well.

The specs of my DOS machines are:

Tiny Purple: 120GB SSD using IDE to SATA adapter, Pentium III running at 933MHz, Aztech Sound Galaxy Pro 16 II (SBPro/WSS/OPL3/Adlib) with NEC Yamaha XG MPU401 Synth Daughterboard, and Compactflash IDE adapter.

Mini Beige: 120GB Maxtor IDE HDD, Pentium III running at 866MHz, Gravis Ultrasound PNP v3, Resound OPL3 with real YMF-262 chip, and Compactflash IDE adapter.

Building the Tiny Purple was a challenge.  I was cramming way more into that little case than it was ever intended for.  This required upgrading the power supply from the stock 40w unit to a 100w unit, as well as adding a fan as it was fanless stock.  This little case is an Acrosser AR-IPC3SP, which has 3 ISA slots.  The one I got used was scuffed up so I repainted it in my favorite color scheme.

Early Aztech sound cards are special.  Often labeled for OEMs like this Packard Bell seen here, they have an onboard EEPROM for settings.  They are mostly jumperless but yet are NOT PnP.  When running early DOS software, you don’t want to waste memory for sound card drivers and these fulfill that need; use a config program to set it up how you please, it writes to EEPROM, and the card stays that way until you change it.  The one seen here is based on Aztech AZT1605 which only emulates SB mono.  I wanted stereo, so I dropped in a card based on Aztech AZT2316 later.

This is the AZT2316 card with the NEC clone of the Yamaha DB50XG daughterboard.  It permits playing MIDI via MPU401/General MIDI with no drivers and awesome sound.

It was an incredibly tight fit in there.  At the top is the Compactflash IDE adapter, then the sound card, then the SBC.  Because they’re so incredibly close together, I put industrial grade electrical tape over the back of the sound card to insulate it, and a piece of anti-static bag between the SBC and the sound card just to be safe.

The stock 40w PSU was not enough for that PIII.  While it COULD fire it up after a few tries, it wasn’t stable.  By sheer dumb luck, I found a 100w PSU with the exact same footprint and hole pattern.  It’s a EOS model VLT100-4000 Quad-Output (+5V +12V -5V -12V) unit.  I custom wired it up to the existing AT connectors in the case using WEGO connectors (wire nuts with levers and multiple holes!!) for the sets of grounds and 5v and soldered the single -5 and -12 leads.  As anyone who often re-wires things knows, soldering bundles of wires can be a royal pain.

Set up for testing round 1!  This is when I found out that the 40w PSU was inadequate for the PIII.  I suspect this tiny case was designed for a 486 SBC.

The unit before I had to cut a hole to install a larger vent fan.

All done and running a BBS intro!  Just wish I had a purple filter for the fan.

The little beige unit was just as complicated to build.  First off, it came with the PCI backplane and ATX PSU.  I had to swap that for an ISA backplane, and then re-wire the PSU from ATX to AT.  Thankfully though it’s a 100w PSU already and didn’t need a complete swap.  The chassis is an Advantech 4 slot model IPC-644BP-15Z.

The mighty Gravis Ultrasound, the DOS sound card of all DOS sound cards.  Many early to mid 90s demos would only produce sound thru a GUS, so if you only had SoundBlaster you got silence.  The GUS is special because it has onboard sample memory, and it’s PERFECT for playing tracked modules like MOD and S3M.  Therefore you get hardware mixing and pristine sound quality; they sound as they were intended to sound in the 90s.

Next I dropped in a Resound OPL3 card.  It’s an 8-bit ISA card with a YMF-262 FM chip and nothing more.  Because the GUS has no FM chip, and FM emulated via wavetable sounds like crap, I put this in.  Therefore the beige PC can play many more types of tunes and games.  The Resound card sounds better than any retro-card with YMF-262 including my favorite Aztech ones.  It’s OPL3 perfection.

This unit isn’t nearly as cramped as the mini purple one.  The GUS, Resound, SBC and Compactflash adapter are installed in that order top to bottom in pic.

The first thing I do when I fire up a retro DOS machine I just built is run the Digital Nightmare BBS intro.  It does various donut animations and plays an OPL3 tune.  Simple but effective for testing, and it’s only a few KB in size.

Cubic Player is a blast from my past.  Listening to tracker files thru the GUS is one of my favorite activities.  When I was a teenager on the school bus in the 90s, I used to listen to MOD files in Cubic Player on my ThinkPad 701C on the 45 minute trip home from school.

Most of my SBC collection, I can choose one for any retro need, even switching them out of builds at will.

I even have  Core2Duo and Dual Xeon SBC!  One on the right is a P166.