The 286 Project

Had a desire to recreate the early DOS experience since all my students have only seen Windows 98,ME,2000 and XP.

First thing was to find a box. Rejected the clone 8088 with 296 upgrade as big and ugly so it went to the curb. Found a very nice compact zenith ZCV-2325-EY, about the size of my laptop but a bit thicker. We used to use these are work with green or orange screens. They are interesting machines, there was a 286 version and a 386.

The 286 uses a backplane riser board with a 16 bit isa bus and the ide/floppy controller. The hd controller is IDE instead of the older mfm interface. There are 3 card slots and the main logic board has 6 x 30 pin simm slots for parity ram. I put in 4 x 256 for a total of 1mb. The floppy controller supports a 1.44 mb floppy. Added a TSENG ET3000AX 8bit 256Kb vga video card and a 3com 3C509b ethernet card. The third slot will be either for a sound blaster or a scsi card for an external cd-rom. I also have the microsoft inport mouse card if i want a mouse...

Next we need a hard drive. The box of really old disks yielded a conner cp-3024 20mb which could not spin up and an ibm wda-l80 with the same problem. But the 40mb seagate ST351 spun up like it was new. A good drive in its day. Set the drive type to 17 in the BIOS and the drive booted to dos 5 with perfect writer, mega paint and power menu! However, it had been compressed with doublespace so I fdisked and re-formatted it.

Booted up with dos 6.2 floppy. Installation of the OS was fine. It runs pretty good.

However, as usual we want to push the envelope - how fast can be make this?

Next steps

Ram - not sure i have any 256kb ram sticks but i have lots of 1meg 30 pin simms. Anyone know if the 286 board can take 4mb? I know the 386 version can.

HD - 40mb drive might be limiting. I should have an adaptec 1541 scsi card around here. They were nice cards and thus i can break the bios hard drive limit and use one of the many scsi drives around here.

Video - need to find a fast ISA video card, the ATI wonder cards might be an idea as the early ones also had a mouse port.

OK - almost finished. Sound is working, onboard video upgraded and working.

Install a double 1.2bm/1.44 mb floppy and remove the compaq floppy. Small mod to the front of the case but both are now working! However, a number of the old 360 or 320kb floppies could not be read. Need to install the old old 360 floppy in a machine in hopes of getting stuff off those.

The network card is not working. The settings are in software and there is a conflict so i can't access the card from the software to change the settings. I need an older card with jumpers so you can set the irq, i/o etc by hand.

I did find the packet driver collection CD and remembered than on the windows NT server CD there is a dos tcp/ip stack (yes microsoft used to sell one!), so now there are two possibilities for getting winsock to run. Found copies of cello, mosaic, gopher, and netscape 1 and 2. Ready to roll once the nic is fixed.

On a totally unrelated note, the NT server has been uplugged after 10 years of reliable steady file/print service. Since i've been running osx server for the macs/pcs it hasn't been doing much - it ran the scanner for a while and was the napster machine. But the scanner was moved and napster is gone and even the IIIp finally died - the last parallel port non-ps printer in the house. I'll remove the 8 64mb 72 pin simms and the 3 36gig 50pin scsi drives and put it on the was quite a feat in its day to get it to use a large boot drive - i had to partition the drive into a 4 gig boot drive and install NT and then patch the os so it would recognize the drive and then to non-destructively re-size the boot partition to take the entire drive. While i don't like microsoft's business practices or their current software, NT was not bad as long as you didn't install anything and of course using it to serve files to mac clients was fairly unreliable (IMHE) but who is to say where that fault lies..


Found the 1540 card so can now install a scsi hd and cd-rom and the adaptec scsi drivers. But while searching for the card i found a Compaq 4504, this was a small form factor pentium 200 with a CD, onboard Ess 18xx audio and a Trio 64 video card and a 2gig quantum bigfoot hd. It had win98 on it and was sluggish as hell.

Reformatted the drive with DOS 7 from win98 cd and downloaded the Wxn3xstart patch to allow wfw311 to work on dos 7. Created a dos7 boot disk from the image and patched io.sys

Rebooted and copied msdossys.inf to c:\ and created a config.sys with device=oakcdrom.sys /D:oemcd001 for the cdrom driver from the windows 98 setup floppy. Added mscdex.exe /D:oemcd001 /L:D to the autoexec.bat Rebooted and we now have cd-rom access from dos.

loaded a few programs and the machine is quite snappy.

Dug around and found my old ms developer network cd's from 10 years ago. Disc 2 has dos versions and windows versions. Also found a copy of microsoft BOB. The goal is to set up the machine to run DOS and WFW 3.11 and Win95 from a single boot and to be able to exit either windows back to DOS. Finding drivers will be the most time consuming part. Tried the MSD diags but it can't tell what nic it has, will have to open it up, it it is compaq odd i can toss it as I have some smc cards and some digital cards with the tulip chipset so getting the network up will not be a problem. Right now i'm running it on a 20" flat screen VGA monitor...should haul out the old greyscale vga to see how it looks. Found a zenith amber rgb in the monitor shelf - it should go to the zenith 286 once i switch the video. Would be nice to find the old zenith/heathkit manuals...

I should explain why a DOS project when i mainly use apples. Well, i was working on a more interesting project - getting WFW to run on a PPC 6100 and ran into some hardware problems, so that is sitting in a box until i have more time. But the idea remained.

Anyway, I did a custom setup of WFW but left off the networking. Once it was up and running i installed the S3 Trio drivers from a floppy and it is now running 800x600 w 256 colors. Beautiful. Also found ESS driver disk for 18xx but it was win95 and did not work.

Took the machine apart to remove the compaq odd nic and noticed it had a PCI slot between the 2 ISA slots. Weird but good. So i can have 2 cards. Question is which 2?

Install a Sound Blaster 16 ISA for sound. But if the ESS sound could be got working this would free up a slot. ESS WFW drivers must exist!

Install an ISA ethernet card. Got a Digital 101 and an 3COM etherlink, just need to set the jumpers for IRQ, i/o and base mem address. With a pci ethernet card we get 100mb but that is not really necessary.

Intall a PCI video card. Now this is interesting - we could really ramp up the video, assuming the compaq bios offers a 'turn off' internal video function. But what to install?

Card Choices (besides the usual tridents and mach 64's)

ATI Rage 128 4mb - fast card
Diamond Stealth 64 - based on S3 Vision 964 gpu. Upgradable ram to ??
Creative CT6710 - has a big heat sink hiding the gpu so not sure what chip it uses or how much ram
Voodoo 3DFX - dual gpus with 12 mb ram! I think this would be the one if there are drivers.

question is - which gives the best performance for dos games and wfw?

Eudimorphodon's picture

Shouldn't you rename this "The Pentium Project", or maybe just "The Dos Project? There's something like a 200x performance spread between what you started with and where you are. ;^)

Regarding specific questions:

(assuming you're still poking at the 286)

gnickers wrote:
Ram - not sure i have any 256kb ram sticks but i have lots of 1meg 30 pin simms. Anyone know if the 286 board can take 4mb? I know the 386 version can.

If the board has SIMM sockets it almost certainly supports 1MB SIMMs. Just make sure they're the 9 or 3 chips ones, not 8 or 2 chip. (Most PC motherboards need the parity bit.) To make it most useful for DOS program in theory it'd be worth checking to see if the motherboard supports turning the "Extended" RAM above 640k into "Expanded" EMS RAM in hardware. A number of last-generation 286 chipsets did. Admittedly to do it you might need a driver that's almost impossible to find.

Back to Pentium-land...

Card Choices (besides the usual tridents and mach 64's)

ATI Rage 128 4mb - fast card
Diamond Stealth 64 - based on S3 Vision 964 gpu. Upgradable ram to ??
Creative CT6710 - has a big heat sink hiding the gpu so not sure what chip it uses or how much ram
Voodoo 3DFX - dual gpus with 12 mb ram! I think this would be the one if there are drivers.

question is - which gives the best performance for dos games and wfw?

If your main target is Windows 3.1 stick with the onboard S3. It's reasonably fast for the era, and drivers for it are dirt common. For strict DOS use the ATI card might be *slightly* preferable to the onboard, because ATI traditionally has had about the best unaccelerated VGA performance in the industry while S3 was semi-notorious for having problems with DOS games. (Specifically, S3 dropped full EGA register compatibility pretty early on.) Also, some older ATI cards, Mach 64 and below, can partially emulate IBM's 8514/A graphics card, which can be slightly useful. Given the card has 4MB... are you *sure* it's a Rage 128? I don't think the 128 comes in configurations less then 16MB. It's probably a Rage Pro or XL.

The other two cards would be mostly wasted under DOS or Windows 3.11. The Creative card looks like it's a RIVA TNT, which would make it the all-around fastest of the bunch, but I don't think you'll easily find drivers for anything before Windows 95. As for the Voodoo, well, is it a "passthrough" Voodoo or an integrated Voodoo+VGA card? (Rush/Banshee). If it's the former and you have DOS GLIDE games to play, throw it in there and use the onboard video for everything else. Otherwise, bin it. The VGA core on the integrated ones is pretty awful.


Now a DOS box until done, and then i'll finish the 286!

Thanks to Eudimorphodon for the excellent tips!. I verified the board needs parity simms. Have to dig thru hundreds of sticks to find some. Also found a CD with windows 1, 2, 2.11 etc on it. Guess i made a backup archive before i tossed the floppies!

Taking the compaq fully apart i discovered 3 neat things - it had an empty L2 slot, two empty video ram slots, and 1 sdram slot!

So, dug out the box of cache stuff and put a 256kb pipeline stick in the coast 3.x slot and an unmarked either pc-100 or pc-66 sdram stick in the ram slot. Did some tests.

When booted with the sdram and no cache the system reported 64mb but with the cache installed it reported 128mb. I seem to recall certain pentium chipsets on boards w/o cache could not handle more than 64mb.

The video slots are for 256k chips of which i have a bunch but the board markings indicate 40ns are required. This strikes me as unusual, all the chips i have are 60ns. So will have to test. If this works, i'll take Eudimorphodon's advice and use the onboard video. This means i can put in the SB 16, disable the ESS sound and use a pci ethernet card.

Finally, i added a 5.25" floppy so that i can root thru the 1000's of old disks for copies of Wordstar, NFL Challenge, etc.

Tried to put in a Canon MD 5511-V6 which is a neat combo small/large floppy in one bay but the front panel is the wrong cutout. So we have 2 floppies so i can make copies for the zenith 286

I could replace the 16x cd with a 52x or how about a cd burner. Anyone burn CD's under dos? Then i could copy the 5.25" disks to CD's.

Finally went into the compaq bios (F10) and made the changes. Rebooted and viola! - one speed demon of a dos box in a very small form factor. Not as portable as my Tandy 1400 or the Apple IIc but very nice.

To do:
- install sb 16
- setup networking

find your old dos tcp/ip stack. I think i tossed the 5.25 floppies but should be able to download an open source one, i used one back in '85 but i can't remember what it was called.

BTW - i have a bag of pci ATI rage 128's - may be 16mb? (2/4 chips)

Jon's picture

RE: RAM limit. The RAM limit may be a Compaq limitation. I used to have an old Compaq Presario 4910 (IIRC) that had a hard limit of 64MB (32MB on board and a single 32MB DIMM). It was a K6 chip, so it might have been using a later chipset than your machine, but it did have cache installed and it would never recognize a DIMM over 32MB as anything bigger than 32.