New MS-DOS Computers: Buying Guide

Dec 12, 2015

NIXSYS builds new computers that run MS-DOS. They are new-production systems, not refurbished or surplus hardware. The current range covers 12 systems in tower and rackmount chassis, priced from $1,000.00 to $1,515.00, and every one has ISA slots for the interface cards MS-DOS applications depend on. Every system ships from Irvine, California with a 2-year parts-and-labor warranty and US-based technical support.

This guide covers the three hardware platforms in the range, how to choose between them, and what to check when moving an MS-DOS application onto new hardware.

Why MS-DOS Is Still in Service

MS-DOS applications run in real mode with direct access to I/O ports, interrupts and DMA channels. That makes them simple and predictable. It also makes them hard to move to a protected-mode operating system. Motion controllers, CNC and machine-tool software, test fixtures and data-acquisition systems written for MS-DOS often talk to an ISA card at fixed port addresses. The software works as long as the hardware underneath it behaves the same way.

When the original PC fails, the practical replacement is a new computer that boots MS-DOS, accepts the same ISA card, and keeps the serial and parallel ports the application uses.

Three Platforms in the MS-DOS Range

Intel Pentium III on the VIA 8601A chipset: NX370 series

The NX370 systems pair an Intel Pentium III processor with the VIA 8601A chipset. Each has 1 full-size ISA slot, 3 32-bit PCI slots, 1 serial port and 1 parallel port. They support MS-DOS, Windows 3.1, Windows 95, Windows 98 SE, Windows 2000, Windows NT 4.0, Windows XP and Linux.

Intel Pentium 4 on the Intel 845GV chipset: NX-i90 and NX-i85 series

These systems use an Intel Celeron or Intel Pentium 4 processor on the Intel 845GV chipset, with 3 ISA slots, 2 to 4 32-bit PCI slots, 1 serial port and 1 parallel port. They support MS-DOS, Windows 98 SE, Windows 2000, Windows NT 4.0, Windows XP and Linux. The NX-i90 and NX-i85 towers also support Windows 3.1.

  • NX-i90: 3 full-size ISA slots, 2 PCI slots; mid tower, $1,075.00
  • NX-i85: 3 full-size ISA slots, 4 PCI slots; mid tower, $1,415.00
  • NX-i290, NX-i390 and NX-i490: 3 ISA slots, 2 PCI slots; 2U, 3U and 4U rackmount chassis, $1,275.00 to $1,375.00
  • NX-i85R: 3 full-size ISA slots, 4 PCI slots; 2U, 3U or 4U rackmount chassis, $1,515.00

Intel Pentium D on the Intel 945GV chipset: NX-i95 series

These systems use an Intel Celeron or Intel Pentium D processor on the Intel 945GV chipset, with 2 full-size ISA slots, 5 32-bit PCI slots, 1 serial port and 1 parallel port. They support MS-DOS, Windows 2000, Windows XP, Windows 7 and Linux.

  • NX-i95: mid tower, $1,175.00
  • NX-i295: 2U rackmount chassis, $1,275.00
  • NX-i395: 3U rackmount chassis, $1,275.00
  • NX-i495: 4U rackmount chassis, $1,375.00

How to Choose

  1. Count the ISA cards. One card fits any system in the range. Two cards need a 945GV or 845GV system. Three cards need an 845GV system.
  2. Count the PCI cards. The 945GV systems offer 5 32-bit PCI slots. The NX-i85 and NX-i85R offer 4.
  3. Check for Windows 3.1 or Windows 95. Windows 3.1 runs on the NX370, NX-i90 and NX-i85. Windows 95 needs an NX370.
  4. Decide on the enclosure. All three platforms come as towers. The 845GV and 945GV platforms are also available as 2U, 3U and 4U rackmount chassis.

Moving an MS-DOS Application to New Hardware

  • Port addresses and interrupts. Record the I/O address, IRQ and DMA channel of each ISA card in the existing machine, along with the settings in the application's configuration files. Reserve the same resources for ISA in the new system's BIOS so the software finds the card where it expects it.
  • Timing-sensitive software. Some MS-DOS programs use software timing loops written for much slower processors. Test any timing-sensitive routine on the new system before it goes into production.
  • Disk partitions. MS-DOS 6.22 uses FAT16, which limits each partition to 2 GB. Plan the partition layout for the boot drive accordingly.
  • Keyboards and USB. MS-DOS has no native USB support. USB keyboards work only through BIOS legacy emulation, and other USB devices need dedicated MS-DOS drivers.
  • Memory and drivers. Copy CONFIG.SYS, AUTOEXEC.BAT and every device driver they load, including HIMEM.SYS, EMM386 and any CD-ROM or card drivers, before decommissioning the old machine.

For the installation itself, see How to Install MS-DOS.

Warranty, Shipping and Support

  • 2-year parts-and-labor warranty on complete systems; motherboards purchased separately carry 1 year. See the warranty and return policy.
  • Most orders ship within 3 to 5 business days from Irvine, California.
  • Returns are accepted within 30 days of invoice.
  • Technical support is based in the US and handled by engineers, not a call center.

Frequently Asked Questions

Can I still buy a new computer that runs MS-DOS?

Yes. NIXSYS currently offers 12 new-production systems that support MS-DOS, priced from $1,000.00 to $1,515.00.

Do MS-DOS computers from NIXSYS have ISA slots?

Yes. Every system in the range has ISA slots: 1 on the NX370 systems, 2 on the 945GV systems and 3 on the 845GV systems.

Is there a rackmount MS-DOS computer?

Yes. Rackmount models are available on the 845GV platform (NX-i290, NX-i390, NX-i490 and NX-i85R) and the 945GV platform (NX-i295, NX-i395 and NX-i495) in 2U, 3U and 4U chassis.

Can the same computer also run Windows?

Yes. Every system in the range also supports Windows 2000 and Windows XP. The Pentium III and 845GV systems add Windows 98 SE and Windows NT 4.0, and the 945GV systems add Windows 7.

Related Guides

Configure and Order an MS-DOS Computer

Request a quote: sales@nixsys.com or call (866) 464-9797.