As for the Tandy 1000, yes it was interesting.
It was almost on par with the Nintendo NES, I think.

There's an emulator for DOS, Tandem, which runs on 386+ PCs.

Horun wrote on 2020-08-17, 04:24:

Actually the XT/3 uses a 8086-10 and most benchmarks never compare that to a 286-6. Maybe you can guess why 😀

I can imagine that a 8086-10 (turbo XT means 8088/v20 not 8086/V30 if you ask me but whatever) *might* achieve parity with a 286-6, but run circles around it? No way

An 8086 is the full cpu where the 8088 is slightly neutered, both are XT class cpu's so not sure where you get that a "Turbo XT means 8088/v20". Likewise a 386DX is a full cpu where the 386sx is slightly nuetered, but you think that makes them not the same class cpu ? Yes just like comparing the late 486 boards and cpu, with the P5 60MHz released with a flawed chipset, many 486 could meet or beat P5-60 performance. The first 286 at 6Mhz were horrid performers due to same thing. Maybe you been in that rabbit hole to long and forgotten all that 😀

Horun wrote on 2020-08-18, 01:20:

An 8086 is the full cpu where the 8088 is slightly neutered, both are XT class cpu's so not sure where you get that a "Turbo XT means 8088/v20". Likewise a 386DX is a full cpu where the 386sx is slightly nuetered, but you think that makes them not the same class cpu ? Yes just like comparing the late 486 boards and cpu, with the P5 60MHz released with a flawed chipset, many 486 could meet or beat P5-60 performance. The first 286 at 6Mhz were horrid performers due to same thing. Maybe you been in that rabbit hole to long and forgotten all that 😀

I have a 5162 that I use regularly

I do not consider the 386sx to be the same class as a 386DX for the record

So... I've done a bunch of reading on the Tandy 1000 PCs... wow, what a rabbit hole to go down. I first played on the Tandy 1000 at my Mom's office when I was a kid, I didn't know they were so basic in terms of hardware. Played Falcon AT and F-19 Stealth Fighter on one before I ever got my own PC (owned an Apple II at the time).

Having said that, there is no perfect solution there either, but it appears either a TX or TL model is the only way to go. They are hard to find ATM however... boo!

Getting the AT feeling... I think I get fairly close with my IBM model 30 286 10MHz, with 1MB and integrated basic VGA card.

I hardly use it. I've got a couple of dozens retro rigs, and my favourites for gaming are the Philips P3105 (8MHz XT, CGA, software turbo) , 386 DX40 (8MB, S3-928) and 486 DX2-66 (32MB, VLB graphics CL542x).

The XT runs everything in this class perfectly.
For faster, there 386 comes to mind, but the 486 runs everything the 386 does but better (except for a few games like TD3).
The 486 runs everything 2D for DOS.
Need faster DOS performance? K6-3+ @win98.

Then why do I have the model 30? Just because of the IBM logo ofc :p I like the model 30 for its looks. Together with 4 other model 30s 8086.

TechDeals wrote on 2020-08-18, 09:47:

So... I've done a bunch of reading on the Tandy 1000 PCs... wow, what a rabbit hole to go down. I first played on the Tandy 1000 at my Mom's office when I was a kid, I didn't know they were so basic in terms of hardware. Played Falcon AT and F-19 Stealth Fighter on one before I ever got my own PC (owned an Apple II at the time).

Having said that, there is no perfect solution there either, but it appears either a TX or TL model is the only way to go. They are hard to find ATM however... boo!

They are great machines for early PC games!

My preferred one is the later 1000 RL model. Small slim, good looking, and with a normal 8-bit slot (just one, but no special Tandy proprietary slot), and mostly normal standard connectors (except joystick ports).

I feel the 286 overlaps the 386 by a good margin as well. I've owned quite a few of both in the last 15-20 years. I myself use a somewhat fast (12MHz) 286 for that era currently....but it almost overlaps my Tandy 1000A and 486s a little too much or so it seems by virtue of the slowdown ("turbo") button. Turbo off almost matches my Tandy perfectly, while most of the stuff I run is the same stuff I run on my NEC Versa 486 DX2 SL 40 laptop with similar results.

The only time I'm really aware there's a 80286 in there is running Windows 3.1.

Id rather have a 286 tbh. Especially a later fast 20/25mhz one.

Those start to enter 386 performance territory and IMO are much more interesting than a 386 machine.

Anything that definitively needs 386 instructions and horsepower would probably be better off on a good 486.

SodaSuccubus wrote on 2020-08-22, 07:09:

Id rather have a 286 tbh. Especially a later fast 20/25mhz one.

Those start to enter 386 performance territory and IMO are much more interesting than a 386 machine.

Anything that definitively needs 386 instructions and horsepower would probably be better off on a good 486.

To be honest, I agree anything a fast 386 does, a 486 does better except for a very few things. A good 16-25MHz 286 is quite capable of doing the stuff the 486 is too l fast for.
Almost anything for the 286 would be fine for the 486 too when you press the turbo button on a fast 486. Or play with enabled or disabled cache.

But OP has already got the 386 and is looking into the AT class. That changes the game a bit 😉

martinot wrote on 2020-08-21, 14:43:

They are great machines for early PC games!

My preferred one is the later 1000 RL model. Small slim, good looking, and with a normal 8-bit slot (just one, but no special Tandy proprietary slot), and mostly normal standard connectors (except joystick ports).

RL? Isn't that a 8086 at 9.54 MHz?

I don't have a good mental idea of the difference between a 8MHz 286 and a 9.5Mhz 8086, having never owned either and only used them rarely as a kid. That is why I was thinking of the TL with a 8MHz 286 and multiple ISA slots.

A TL/3 appears to be the perfect machine to me, 10MHz 286 and a HD floppy controller for 1.44MB floppy drives.

Odds of finding a good example? Poor
Odds of finding a good example for a fair price? Almost impossible!

creepingnet wrote on 2020-08-22, 06:54:

I feel the 286 overlaps the 386 by a good margin as well. I've owned quite a few of both in the last 15-20 years. I myself use a somewhat fast (12MHz) 286 for that era currently....but it almost overlaps my Tandy 1000A and 486s a little too much or so it seems by virtue of the slowdown ("turbo") button. Turbo off almost matches my Tandy perfectly, while most of the stuff I run is the same stuff I run on my NEC Versa 486 DX2 SL 40 laptop with similar results.

The only time I'm really aware there's a 80286 in there is running Windows 3.1.

My 386 is WAY overkill for CGA/EGA stuff, with a 40Mhz clock speed, 8MB of RAM, ET4000 video card, and 17" SVGA CRT monitor (which is really too big for this, but it's what I have)

Also, it is a boring generic case and my OP question about the IBM AT had as much to do with how it looks as anything else. A real 5170 with a real 5154 would look nice on my desk.

I also was under the impression that a 8MHz 286 would effectively cover everything from 1981 to the late 80s.

SodaSuccubus wrote on 2020-08-22, 07:09:

Id rather have a 286 tbh. Especially a later fast 20/25mhz one.

Those start to enter 386 performance territory and IMO are much more interesting than a 386 machine.

Anything that definitively needs 386 instructions and horsepower would probably be better off on a good 486.

You're probably not wrong... however I'm in the process of putting together those parts as well. I have a 486 MB with ISA/VLB/PCI and a AMD 5x86 P75 and 32MB of RAM, so I'm covered there... but THAT will end up being my ultimate DOS PC for gaming in the mid-90s before Windows completely took over. I haven't decided on a video card yet, VLB or PCI, there seems to be pros and cons to both. It will have a SoundBlaster AWE64 however. 😀

The 286 is as much for the experience of an era that I just missed, and I honestly probably would only want a Tandy TL or IBM 5170 at this point for the history of the machines.

You could look into the IBM model 30-286 if you want history. PS/2 brought us a lot of standards, including VGA and the mini din keyboard and mouse connectors.

The model 30 isn't that fast, even for a 286 I'd call it slow. But having 16b ISA on a PS/2 makes it compatible with the market (instead of the never adopted MCA on other models). The VGA also seem compatible with some CGA capable titles I've thrown at it (alley cat, digger, street rod in CGA mode, Grand Prix).

I personally do not have the 286 Model 30 (only the normal Model 30), but I agree that is a great 286 machine to have. More compact than the much bigger (but better looking) AT, and like you point out with better more modern connections (PS/2 keyboard, mouse and VGA monitor support). Would love to have that 286!

TechDeals wrote on 2020-08-17, 06:18:

For some reason I have it in my mind that I could replace the 8Mhz 286 chip with a 12 or 16Mhz CPU, but that might not be possible. Does it matter for EGA games? I don't know.

Be careful with that line of thinking. I'm not sure the original AT had decoupled the CPU from the expansion bus yet -- the clock wasn't high enough to cause issues yet, so it may be stuck in lock-step. I don't know about you, but I don't fancy my chances of running any ISA cards at 16MHz, even if you manage to get the board-resident hardware stable at that speed -- also a crapshoot considering it was chosen with a 6-8MHz clock in mind.

A 286-8 with EGA ought to be servicable for everything up to around 1988 or 89 I'd imagine, but I wouldn't want to be the one stuck trying to run Windows 3.x on such a slow CPU.

Correct, 5170 expansion bus runs at the same clock as the CPU.
There are parts in the AT that also might prevent reliable overclocking. The memory chips probably need to be replaced with faster ones, as well as the 82288 bus controller and 82284 clock driver/ready interface. The DMA controllers probably also don't react well to being pushed too hard.
Last winter I started looking into the possibility of adding a clock divider to the AT bus. It seems doable. But, 12MHz might be as far as the AT can be pushed, because the fastest available 82284 and 82288 chips available are 12mhz parts.

TechDeals wrote on 2020-08-17, 06:18:

In terms of the system itself, I'm assuming that I'd end up upgrading the internals to whatever "the best" they would support, within reason. For some reason I have it in my mind that I could replace the 8Mhz 286 chip with a 12 or 16Mhz CPU, but that might not be possible. Does it matter for EGA games? I don't know.

That is probably not easy. You would need to also change the crystal that sets the bus speed, and the original AT probably didn't have components that could run at the higher speed, as they weren't needed at the time.

waterbeesje wrote on 2020-08-22, 13:32:

You could look into the IBM model 30-286 if you want history. PS/2 brought us a lot of standards, including VGA and the mini din keyboard and mouse connectors.

The model 30 isn't that fast, even for a 286 I'd call it slow. But having 16b ISA on a PS/2 makes it compatible with the market (instead of the never adopted MCA on other models). The VGA also seem compatible with some CGA capable titles I've thrown at it (alley cat, digger, street rod in CGA mode, Grand Prix).

That's a solid suggestion... that only doesn't work for me because I lothe the PS/2 line for some odd reason.

Also, I actually don't want VGA on this, I think its out of place on a 286, but that's me. Tandy graphics maybe, or EGA, but that's it.

However, thanks for the pointer!

Anonymous Coward wrote on 2020-08-24, 14:14:

Correct, 5170 expansion bus runs at the same clock as the CPU.
There are parts in the AT that also might prevent reliable overclocking. The memory chips probably need to be replaced with faster ones, as well as the 82288 bus controller and 82284 clock driver/ready interface. The DMA controllers probably also don't react well to being pushed too hard.
Last winter I started looking into the possibility of adding a clock divider to the AT bus. It seems doable. But, 12MHz might be as far as the AT can be pushed, because the fastest available 82284 and 82288 chips available are 12mhz parts.

Roger, Roger... canceling any plans to change the chip... I had forgotten about the clock crystal thing!

Now to find a nice Tandy 1000 TL or 5170 in nice condition.