Hardware choices for my retro-utility/gaming rig

What hardware goes into a machine that exists for the purpose of interfacing with old hardware and software?

Number Nine GXE 2MB ISA (S3 928)

The GXE is an example of newer technology being retrofitted into older form factors. The 928 was S3’s next-generation true-color accelerator, mostly sold in VLB form factor. But ISA cards were also made, making it possible for an ISA-only system to outperform the benchmark Tseng ET4000. This card has excellent performance whether in Windows or in DOS mode. Minor graphical glitches in Second Reality during scrolling scenes is all that can be complained about. It ships with S3’s VBE/Core 2.x BIOS enabling VESA linear framebuffer modes. Also, the 928 was the first chip to support the technique used in the S3SpdUp utility for faster VBE 1.2 (banked) and Mode 13h rendering.

Here is a post with benchmarks of various ISA and PCI video cards under DOS.

Creative Sound Blaster 16 SCSI-2 + CSP + Wave Blaster II

What else can be said? This card is the gold standard of PC audio, running software designed for the Ad Lib, Sound Blaster, Sound Blaster Pro, and Sound Blaster 16. It is rare to find a piece of software that does not support one of these three cards as a primary target. The ASP/CSP coprocessor, running at 12 MIPS with 16K program RAM and 8k data RAM, along with the provided firmware, provides several realtime compression codecs. The Wave Blaster II is the standard General MIDI upgrade targeted by games of the time. The SCSI port is used to attach a CD-ROM drive, so the hard disk and CD-ROM are not contending for the IDE bus. And don’t forget the joystick port. The drawbacks of the SB16? Failure to support MPU-401 intelligent mode, failure to support the SBPro-compatible stereo mode, and failure to support the multichannel hardware mixing that the Gravis Ultrasound (and Amiga…) supports. Also, since this is a SCSI-2 model, the DSP version must be checked to assure that it does not contain a bug that causes wavetable card hangs. My card has a revision 4.05 DSP, so it does not have this bug.

Roland MPU-401AT + Roland MT-32

The MPU-401AT hosts a Roland MT-32, which is the most popular non-GM MIDI synthesizer supported by games. While it is possible to plug the MT-32 into the Sound Blaster using a joystick-port adapter cable, there are quite a few programs targeting the MT-32 which will not function without the true MPU-401 “intelligent mode”, which the SB16’s MPU-401 implementation lacks.

Genius RTL8019 NE2000 compatible network card

There is not much to say; one NE2000 card is as good as another. This card is configured to use an ODI stack (LSL, NE2KODI, IPXODI), which allows for Samba client and server in DOS mode, IPX for games, a packet driver (ODIPKT) for DOS WATTCP applications, as well as seamless WFW 3.11 networking support on top of the stack. What is nice about it is that its resources are software configurable, so there are no jumpers to cause a hassle.

SIIG 16-bit Enhanced IDE + I/O

This card supports serial ports up to 230400 bps and an ECP parallel port. On top of that, it has an integrated BIOS that automatically programs the EIDE controller to the fastest timings and replaces the system INT13 BIOS. Therefore, there is no need for Ontrack Disk Manager or anything similar in order to support multi-gigabyte hard drives.

Central Point Deluxe Option Board

This card can transfer files to and from 400k and 800k Macintosh disks, making it very useful for interoperating with Classic Macs. (Capability of reading those disks was dropped from Macintoshes themselves in the mid-1990’s.) It can also copy and/or image almost any copy-protected program disk in existence. It can generally copy FM, MFM and GCR disks, including those from Commodore, Apple, and Atari systems, but cannot copy any non-IBM disks which employ copy protection.

Diamond Computer Systems Trackstar E + Disk ][

This card is a clone Apple //e on a card! It has a plug for a real Disk ][ which I fed through one of the “port holes” in the case. It can display 40 and 80 column output on the DOS display and has a composite output for graphics. It can be used to create images, copy disks, and transfer files to and from Apple ][ compatible 5 1/4″ floppies. As useful as the Option Board is for supporting a Classic Mac, the Trackstar is useful for supporting Apple ][ series systems, if the Trackstar itself doesn’t suffice for your Apple ][ needs.

1.44MB and 360KB floppy drives

While the Epson SD-800 combo 1.44/1.2MB drive is a favorite among oldskool builders, I didn’t use it. The head width on 1.2MB and 360KB drives is different, so if a track on a 360KB disk is written in a 1.2MB drive, it cannot be read in a 360KB drive later. Not much is being sacrificed, since there are very few commercial software titles that shipped on 1.2MB disks compared to 360KB, and even fewer that have any sort of copy protection that prevent using simple disk images. The 360KB drive is connected as drive B:, so to run “booter” floppy games, I use the “BOOT_B” utility.

MSI MS-3125 with AMD 386DX-40, Intel 387DX-33, 128K L2 Cache, 16MB RAM

This is a very fast 386 motherboard with 7 16-bit slots and 1 8-bit slot. It has 128K of cache (maximum 256K) and eight 30-pin SIMM slots with 16MB installed (maximum 32MB). (I was advised to install only 16MB due to the DMA “memory hole” at the 16MB mark.)

This motherboard has support for turning off the L2 cache as well as introducing a large amount of DMA and I/O delay cycles. For example, all three of these things turn out to be necessary in order for the Option Board to correctly write certain high density disk images.

The ability to slow down the motherboard timings is important for certain hardware, like old disk controllers and the Option Board, as well as “booter” games. But using a 386 CPU instead of a 486 CPU is also a good choice. The reason is that the 486 has an 8k L1 cache that must be disabled by software. This is one more BIOS setting that must be toggled back and forth to handle old software with timing loops — if the BIOS even offers the option! Using a 386 CPU removes this potential piece of complication.

However, the 386 does not have an integrated FPU like the 486DX, so programs that depend on floating point operations will run slowly. For a 40MHz 386, there are very few coprocessors available, since only a few specific clone 80387’s actually were rated for 40MHz. Fortunately, the Intel 387DX has an interesting quirk — it can be clocked separately from the CPU, unlike any other 80387 clone. Unfortunately, the 386DX+387DX combination is not quite as effective as the 486DX with its integrated FPU, due to the latency of the bus traffic implicit in the 386 FPU architecture.

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