May not be official but HT12 does run at 20MHz/WS0.
So Harris-20 is fine.
This is why my Octek Fox 2 is my "dream" 286. Except that its CPU is soldered so it doesn't make a good test bed. And -25 is a bigger dream 😉
And the CMS chips too! I've never had any.
I'm not sure about the VGA, I like CL-GD542x but I don't know if it's fully period correct.
4MB of SIMM RAM is great too - though 16MB in 286 is not unprecedented. It just came with caveats in the Hedaka board I once had (had to setup and reset again, maybe twice, after reset, to make it recognize it) and wasn't very useful. HT12 with 4MB of WS0 RAM and active EMS support (can play big mods with GLXPlay through a GUS) beats it hands down.

Desktop case w/ hinged cover, hmmm, that would be nice! And a real dream, a MHz display with a working decimal point. Okay, this 286 does't need it... but it's a dream too!

Personally I hated the AT clones with hinged cover, as they were commonly of low-end (very thin sheet metal that gets easily deformed).
HT12 is definitely the way to go, hardware UMB as EMM as well, and the other configurable stuff is great as well. There is no better 286 chipset to my knowledge.
The best period-correct VGA would be ET3000 (least compatibility problems).
And using a ST-157A, well, I won't do that, as I hate this drive for its sticky heads, but it would be appropriate for a clone ;D
And yes, consider using Compaq MS-DOS 3.31 to not cross the 1990 dateline 😀

I really like the topic of this thread! 😁

HanJammer wrote:

Probably all of us agree that 5170 (or maybe 5162 because of 0 ws memory?) is the king of the hill. But clones were interesting as well.

Some 5170 owners even turned their original IBM into a clone system on their own will.
They replaced the oudated AT-BIOS with a modern Quadtel BIOS (no more fixed HDD entries, no more CMOS setup disks! Yay!).
I forgot where I exactly I know this from, but apparently, it was a popular upgrade, I remember. 😀

Ah yes, for me my dream late 286 (and possibly not so period correct 🤣) build would be like that:
CPU: 25Mhz Harris 286 w/i287XL

Memory: I would've tried to max out what the mobo can support in ram, of course it would be 0-wait state memory. But 8mb w/o wait states is my minimum criterion.

Graphics: Tseng ET3000 for sure but for the monitor I'm torn between à VGA to BNC cable connected to a Sony PVM-1442QM (since it can do either CGA or analog RGB) or a NEC MultiSync II. If it's not period correct then we fall back to a ATI Wonder EGA with paired with a IBM 5154

Hard drive: Seagate ST-296N x2 (I love SCSI hard drives 😜 and two of them because one for programs and games, the other for DOS installations) or two Seagates ST-251 (these drives are rock solid, the grand old soldiers of the MFM/RLL era)

Floppy drives: 3½ and 5¼ (possibly one that can do both 360k and 1.2M without problems)

Motherboard: no preference, as long it has either a Dallas RTC clock chip (no leaky battery) or a NiCad battery but far away from the mobo

Soundcard: I'm torn between a Soundblaster Pro II or a Soundblaster Pro 1.0 (SB16 is a fallback) I doubt a CT1350B w/ CMS upgrade would work, given that CT1350Bs are said to not to play nice with fast CPUs

Other: Adaptec SCSI card, not sure which models would be early 90's period correct or a WX2 MFM controller if I go the MFM hdd route.

Case: Preferably a very roomy case with at least four 5¼ bays (a la IBM 5162), with the turbo button and reset button on the front, Power switch position isn't important for me.

Keyboard would be a Model F AT clone or one with complicated Alps hands down 😁

retardware wrote:

Personally I hated the AT clones with hinged cover, as they were commonly of low-end (very thin sheet metal that gets easily deformed).

I have different observations 😀 Each hinged case I've seen had very massive sheet metal. Same is the CASE ;d with two of them I have now...

Jo22 wrote:

I really like the topic of this thread! :D Some 5170 owners even turned their original IBM into a clone system on their own will […]
Show full quote

I really like the topic of this thread! 😁
Some 5170 owners even turned their original IBM into a clone system on their own will.
They replaced the oudated AT-BIOS with a modern Quadtel BIOS (no more fixed HDD entries, no more CMOS setup disks! Yay!).
I forgot where I exactly I know this from, but apparently, it was a popular upgrade, I remember. 😀

Yeah, that would be probably first thing I would do 😀
Still it remains original hardware just with different software running on it 😀

HanJammer wrote:

I have different observations 😀 Each hinged case I've seen had very massive sheet metal. Same is the CASE ;d with two of them I have now...

The early ones were almost bullet-proof thick, you could put a 13-15" monitor on top and not worry about any long-term deformation. Later though they've started to make them from thinner sheets, and while it reduced the weight it also meant the case would bend under a CRT monitor. Especially since monitors started to grow in size and weight as well.

Vynix wrote:

w/i287XL

Oh, I forgot this part... well, anything that's not the bog standard i287. Something cooler and faster and... well, cooler 😁

I don't think I ever really dreamed of a 286 - by the time I had a 286 I was dreaming of 486s - Before that I had a TRS-80 and was dreaming of Amigas, but if we are shooting for period correct...

Intel 286-12, 1MB RAM, big 70MB+ full height MFM drive (I go for SCSI, but then I couldn't bare to use a period correct drive). For me a 286 has to have EGA (or maybe hires mono like Wyse WY800) - I know many 286s (and even some XTs) came with VGA, but anything I'd want to play in VGA I'd want to play on a 386 or better. For the same reason I wouldn't install a soundcard - when I played on a 286 I played with PC speaker.

Well, my actual 286 is like this:
Harris 286-20
Headland chipset
Desktop case
4 MB memory
ET4000/W32 graphics
Sound Blaster Pro 2
GameBlaster clone
Tandy Clone soundcard
IBM Music Feature Card

HanJammer wrote:

Probably all of us agree that 5170 (or maybe 5162 because of 0 ws memory?) is the king of the hill. But clones were interesting […]
Show full quote

Probably all of us agree that 5170 (or maybe 5162 because of 0 ws memory?) is the king of the hill. But clones were interesting as well. So what would be your dream 286 build and why? Which motherboard and chipset? CPU? Graphics card? Sound card? Case? Also let's stick to period correct parts (so let's say 80's to early 90s).

For me:
Case: desktop case with side switch (L-shaped PSU), LED segment display and hinged cover.
CPU: Harris 20Mhz or 25MHz...
RAM: 2-4 MB in SIPP modules? Or maybe 1-2 MB in DIPs… I don't know…
Chipset/motherboard: I have no idea... maybe HT12? Or some Suntac… Perhaps both not compatible with 20Mhz at all… I can't decide yet…
Graphics: No idea... 🙁 too many fascinating options here.
Sound: AdLib. Or CT1350B with CMS chips... and obligatory Covox!
HDD: ST157A!!!
Floppies: 3,5" and 5,25" Canon or Teac…
What else?

I have a Vega Video 7 card that's been waiting for a 286 home for literally decades. Still in its box. It has both 15 pin and 9 pin outputs, and can support MDA, Hercules, CGA, EGA and VGA. Only has 256k of video ram (iirc). It's my plan to stick that video card in the 286 I'll hopefully be able to build here in a few weeks (it's only a 10mhz motherboard, but it's a 286.) Part of me wants to hoard the card, part of me wants a more powerful VGA card, but this just seems to perfect to pass up.

Your specs are about what I would want, otherwise. Oh, and you left out 3Com Ethernet card.

dr.ido wrote:

I don't think I ever really dreamed of a 286 - by the time I had a 286 I was dreaming of 486s - Before that I had a TRS-80 and was dreaming of Amigas, but if we are shooting for period correct…

Well… 286s are like a stinky cheeses - not for everybody's taste 😉
I hated my 286 when I had it (until early 1997!) and I would replace it for anything better without second thought.

But from time's perspective - I had so much good time with this computer… and I learned alot too…

So yeah - my taste for 286s is strongly nostalgia-related 😀

PS: I started this thread partially because I'm looking for inspiration for my next (second) 286 build. 😉

Anyone know if the C&T SCAT chipset is any good? It's newer than NEAT, so it might be comparable to the HT12.

My dream 286 is a fully loaded IBM AT. It should be EGA, with an 84-key keyboard and it should have an MT32. The Music Feature Card is nifty, but useless!
If you can't get a real IBM, then at least get an Everex...and failing that, at least make sure whatever you have is in a full size desktop case!

I'm really happy 286s are finally getting some attention on VOGONS. They may be braindead, but they're a lot of fun.

I remember on uncreative labs many years ago there was a guy named "casolai" who really pushed his 286 setup to the limits. I think he had a Mach64 and was running Windows 3.11 (the non workgroups version).

https://web.archive.org/web/20000919041058/ht … asolai/286.html

My dream build uses stuff that I design myself but that's a long way off 🤣.

*Can use fastest 286 flavors + FPU
*Waitstateless operation for the CPU in all circumstances
*Bus mastering storage controller (no CPU data copying and IO bottlenecks)
*Chipset based EMS
*USB HID devices support
*Fancy BIOS that can provide lot of stuff without requiring drivers to be loaded, saving precious low memory and UMBs. That's gonna be a hard thing to do...

dr.ido wrote:

big 70MB+ full height MFM drive (I go for SCSI, but then I couldn't bare to use a period correct drive).

If you want a drive that matches exactly this period, why not go for a mid-late-1980s 70MB Imprimis drive?

Like this 71MB Imprimis Wren II?

When you look at the images you will understand why Seagate bought Imprimis (iirc in 1989) to give themselves a big technology and quality boost.
And you'll understand why before that Seagate drives were considered as utter crap by storage professionals.

(FYI: Imprimis was the name of the spun-off hard drive division of Control Data Corp, which was in financial crisis.)

BTW do any of you guys know what is the difference between Headland HT12 and Headland GC102/HT102 chipsets?

HanJammer wrote:

BTW do any of you guys know what is the difference between Headland HT12 and Headland GC102/HT102 chipsets?

I'm speaking under correction, but I believe the 102 is older and can't provide Expanded Memory (EMS) or UMBs.
It (besides the G2, alternatively) was used in the Schneider Euro AT series and the Schneider Tower AT models.

I have three 286 boards atm, one with an AMD N80L286-16/S (soldered on), another with a Siemens SAB286-16-N (soldered on). However, the 3rd board has a Harris CS 80C286-16 (image attached) which is socketed. I'm thinking of upgrading it with a higher clock speed, there is a 20Mhz Harris for sale on eBay [1], but I don't think this board supports it though.

[1] https://www.ebay.com.au/itm/CS80C286-20-CPU-1 … is/311083581303

I have Harris 20MHz on Octek Fox III - same chipset...

@JanHammer. Nice one. I assume you have a 40Mhz crystal then (probably the one near the power intake)?