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386 on a 286 board? AKA, thought I bought a 286, got a 386 instead!

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ardsleytank

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So, I'm new to the world of IBM Compatibles, so please pardon me for any inaccuracies I may make.

So, I recently bought an AT-clone, with Packard Bell monitor for a steal of a deal. (Well, I haven't tested it, but the parts alone were worth it)

Anyway, I was digging into it, trying to see what speed of CPU I had, when I made a rather shocking discovery: It has an Am386 DX/DXL in it.

The case says it's a 286, but it appears to have been updated over its life, including dual ST-225 40MB HDD's, a 1.2MB FDD, and a 1.44MB FDD, and of course, an Am386. It also has an EGA card. I'm not sure of the RAM, but according to the case, it at least started life with 640K, but without booting it up, I have no idea how much is actually in there...

Anyway, was this a thing back in the day? Swapping in a 386 into a 286 computer? It appears to have last run somewhere between 1993-2000, as those are the dates I have found inside the case.


Many thanks,
Peter
 
The 286 and 386 CPU families do not share sockets, so it's not like someone just dropped-in that 386. The motherboard would have been swapped, along with the RAM.

It appears to be a rebuilt machine.
 
AT is synonymous with 80286. You have a 386, but this is much better, as any CPU 386 or higher supports the all-important "protected mode" - meaning it can run 'real' OS like Linux and BSD.

So, have you considered running Linux on it?
 
Not really, I'm not too familiar with Linux, so I'll probably stick to some version of MS-DOS. What are some advantages to running Linux on a system like this?
 
ardsleytank said:
Not really, I'm not too familiar with Linux, so I'll probably stick to some version of MS-DOS. What are some advantages to running Linux on a system like this?
Click to expand...

For 99.9% of people there are zero advantages to it. For the 0.1% there is some fun in running a vintage linux flavour 'just because'.

There is very little useful software available that will run on a 386/linux system.
 
Hmm, I see.

So, here's a question. Is my computer less desirable than say a "normal" 286 clone? Given the fact that it looks the part, but is actually not a legitimate AT-286?

Just curious, as I am mildly disappointed with this discovery. It looks the part nonetheless, it can run everything a 286 can plus more, so, I'm not too bothered, just wondering how the community views these types of hodge-podges... (I know that in the classic car community, "period correct modifications" are seen as an acceptable thing, not sure about here though)

I guess you could call it a sleeper-PC... :cool:;)

Peter
 
ardsleytank said:
Anyway, was this a thing back in the day? Swapping in a 386 into a 286 computer? It appears to have last run somewhere between 1993-2000, as those are the dates I have found inside the case.
Click to expand...
Absolutely! The ENTIRE REASON for someone putting together or buying a generic AT form clone was so one could upgrade components without having to throw the entire thing away.

Buy a 286 now... upgrade just the motherboard a year later when you have more money and 386 prices are cheaper anyway. Or perhaps the case just came with a generic "286" badge and the person who built it just put that badge on anyway.

A generic AT case may hold up to a Pentium 1 motherboard, or AMD-K6.

A machine I have went from 286 to 486 to Pentium 200... and now back to 286 :p

I know, it is almost unthinkable these days as everyone just throws things away when the integrated batteries die.
 
ardsleytank said:
So, here's a question. Is my computer less desirable than say a "normal" 286 clone? Given the fact that it looks the part, but is actually not a legitimate AT-286?
Click to expand...
If there's a "286" somewhere on the case, but inside it's a 386, then yes, it's ugly, and I tend to avoid such things.
The difference between 286 and 386 is huge, 286 is 16-bit, ie. absolutely vintage, while 386 is 32-bit, and 32-bit platforms are still in wide use.
However, there are 386 boards that are precious, see eg. those early ones, with lots of discrete chips, instead of later highly-integrated chipsets.
 
It's not unreasonable. I built my main i7 rig is built into a 386-era AT server chassis (I modified it for an ATX motherboard, and rebuilt the PSU with the guts of a modern 1200W PSU) that originally housed hull height 5.25" SCSI drives. I recall a rumour that you could at one point get a Pentium board that would fit a Tandy 1000 EX/HX case, but don't take my word on that.
 
WimWalther said:
The 286 and 386 CPU families do not share sockets, so it's not like someone just dropped-in that 386. The motherboard would have been swapped, along with the RAM.

It appears to be a rebuilt machine.
Click to expand...

While they didnt share a socket, you could get a 386 to mount in a 286 socket on a little daughter board, you then ran a program on your PC to enable the cache. I bought one for the 286 machines at work as a trial, but the interrupts operated differently, which was OK on a PC, but didnt work with the industrial PIBUS interface cards.

I ended up putting it in my AT desktop, so there is at least one AT out there with a 386 (probably in a cupboard at work somewhere)
 
In bought a 286 machine shortly after they came out and was rather disappointed in it's performance. I kept it for about a year and sold it to help pay for a new 386 machine.
There was quite a difference in the performance and ability to multitask programs under Windows 3.1. It was soooo much more useful than the 286.

I never regretted that decision and to this day feel that a 386 is far more collectible that any 286.
 
Chuckster_in_Jax said:
In bought a 286 machine shortly after they came out and was rather disappointed in it's performance. I kept it for about a year and sold it to help pay for a new 386 machine.
There was quite a difference in the performance and ability to multitask programs under Windows 3.1. It was soooo much more useful than the 286.
Click to expand...
You know, 286 PCs came out in 1984 (IBM 5170), and a year later 386 PCs weren't there.
If you're talking about the Windows 3.1 era (1992), then 286 was already low-end, or even obsolete, so no wonder its performance was disappointing.
 
I wasn't aware that utility was a determinant of collectability. That Apple I isn't terribly utilitarian. The IBM 5170 is historically noteworthy because it was the first in IBM's product line to employ an MPU capable of protected mode operation (not counting the 68K based lab computer). It made Windows workable and Unix practical on the PC platform.
 
Xacalite said:
You know, 286 PCs came out in 1984 (IBM 5170), and a year later 386 PCs weren't there.
If you're talking about the Windows 3.1 era (1992), then 286 was already low-end, or even obsolete, so no wonder its performance was disappointing.
Click to expand...

I distinctly remember my Zenith 286 coming with Windows. It is possible that it came with ver 2.0. I don't believe I still have the sales receipt for it and I would have to look it up in an old sales catalog to confirm that. We also had an HP Vectra 286 at work with Windows on it.

Chuck(G) said:
The IBM 5170 is historically noteworthy because it was the first in IBM's product line to employ an MPU capable of protected mode operation (not counting the 68K based lab computer). It made Windows workable and Unix practical on the PC platform.
Click to expand...

Protected mode on a 286 was termed "neglected mode".
Take a look at this WIKI on Protected Mode to see why. It discusses the shortcomings of the 286 and improvements that came about with the 386.

https://en.wikipedia.org/wiki/Protected_mode
 
People were still tied to 16-bit real mode for quite some time after the introduction of the 80386. It was a pet gripe of a friend at Intel.

On the other hand, when the only other arrow in your quiver is an 8088, you'll do what it takes. A couple of friends developed an orbital mechanics package for the 80286 that would have been difficult and slow if done on an 8088. There are other examples.
 
Chuck(G) said:
The IBM 5170 is historically noteworthy because it was the first in IBM's product line to employ an MPU capable of protected mode operation (not counting the 68K based lab computer). It made Windows workable and Unix practical on the PC platform.
Click to expand...
It did even better than that.

Back in the 1980s I was working at the National Weather Service Forecast Office in Philadelphia and we had a Compaq 286 that was running Unix. That workhorse combo ran eight programs simultaneously 24/7/365 without any issues.
 
Chuckster_in_Jax said:
I distinctly remember my Zenith 286 coming with Windows. It is possible that it came with ver 2.0. I don't believe I still have the sales receipt for it and I would have to look it up in an old sales catalog to confirm that. We also had an HP Vectra 286 at work with Windows on it.



Protected mode on a 286 was termed "neglected mode".
Take a look at this WIKI on Protected Mode to see why. It discusses the shortcomings of the 286 and improvements that came about with the 386.

https://en.wikipedia.org/wiki/Protected_mode
Click to expand...

I have a Zenith 286, and it came with Zenith MS-DOS 3.2 & Windows version 1.

If memory serves, Bill Gates once called the 286 "brain damaged."
 
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