NuXT motherboard - A May-December Marriage Of Technology

One of the biggest hurdles to overcome in the Retro Computing world is obtaining period correct parts. The older the computer is, the harder and more expensive it becomes to put together a complete system. Everything from expansion cards to the keyboard and monitor are all from a bygone era. This is especially true for PC/XT class computers. The NuXT motherboard tries to address all of this while staying true to this type of computer from the 1980s. The NuXT is sold by Monotech Vintage PCs out of New Zealand. Here is a list of features and a few pictures:

• 8088 and NEC V20 CPU support
• 8087 math co-processor support
• 9.55MHz, switchable to 4.77MHz or 7.16MHz on the fly
• Dual 64K ROM, switchable with DIP switch, writeable
• 832K RAM
• 640K conventional
• up to 192K UMB RAM (160K max when using VGA)
• UMB-Configured DOS 6.22 uses only 10K conventional!
• PC/104 Expansion Platform
• (optional) PC/104 SVGA card, with VGA port in the rear I/O area
• Real-time clock (uses a CR2032 cell)
• High-density Floppy controller, with FM support
• Bootable XT-IDE Interface
• Onboard IDE port
• Onboard CompactFlash card slot at rear I/O
• (optional) 64MB CF Card Included! Loaded with DOS and ready to go
• 16550 Serial Port
• PS/2 Mouse Port
• PS/2 Keyboard Port (can be jumpered for XT keyboards)
• Bidirectional parallel port
• ATX Power Input. Generates own -5V rail
• 4 x 8-bit ISA Slots
• Front-panel connector for modern cases
• Can disable onboard peripherals and adjust resources used

The best way to describe the NuXT motherboard is a mATX retro motherboard that can be used with a contemporary computer case and peripherals. This nearly eliminates the need to hunt down period correct parts like a keyboard and monitor. I have the newest revision of the motherboard which is currently at v2.0. I had to make some design choices when doing the build and I ended up choosing the following:

 

Case – InWin BK623

Floppy drives – 1.44MB 3.5” & 360K 5.25”

Networking – 3Com Etherlink III 3C905B

Sound – Creative Labs Sound Blaster 16 CT4170

EMS board – Lo-Tech 2MB EMS board

Hard Drive – SanDisk Ultra 2GB CompactFlash card

 

I chose the InWin case because it is very compact and accepts full height addon cards. The 1.44MB 3.5” diskette drive is 100% compatible with older 720K diskettes and much cheaper than a 720K 3.5” drives will cost you. I went with a 360K 5.25” diskette drive because almost all PC/XT class systems had a 360K drive and not a 1.2MB like in the PC/AT. I was lucky enough to find a new old stock one on eBay that did not break the bank. The 3Com 3C509B network card works well in an 8-bit slot, but it has to be configured in a system with a 16-bit slot first. These cards can be had for under $20 on eBay. I chose the Sound Blaster 16 CT4170 because it works well in an 8-bit slot and these are usually under $20 on eBay. The EMS board from Lo-Tech works extremely well and it is much smaller versus an actual EMS board from the 1980s. These boards come in at about $78. I have found that SanDisk Ultra CompactFlash cards are compatible in every retro computer I have used them in. I have not had great luck using other brands which were hit and miss. I was lucky enough to find a batch of used ones on eBay for $5 each.

Here are few pictures of my build:

I am running MS-DOS 6.22 and use the MTCP TCP/IP suite from Mike Brutman for connecting to my home network and the Internet. I currently have about 500MB of software on the 2GB CompactFash card. I use Win32 Disk Image for backing up. This makes restoring a breeze. I can do a complete back up or restore in under 10 minutes. So how compatible is the NuXT versus having an actual IBM PC or clone computer from the 1980s? I have not run into any issues myself but having an onboard VGA does not support CGA composite video output which some people may wish to use. Luckily, the onboard VGA can be turned off via a dip switch. You can then install a CGA, Hercules, or EGA graphics card of your choosing. Is the NuXT motherboard worth the price. I got mine fully loaded and it cost $367 plus $40 shipping. For some that may be a bit too steep. I personally think the convenience you gain will make the money you invest in it now more valuable over time. Retro computing equipment from the 1980s is only going to get more expensive and harder to find as time goes on. 20 years from now getting a PS/2 mouse or keyboard and a monitor with VGA connector will be much easier than finding vintage 1980s parts. I think that makes the NuXT worth it as an investment for the future.