Intel486dx33 wrote on 2020-02-07, 10:49:

My 486 can run games intended for an IBM 5150 just fine.

I can't remember the name but there was this plane dogfighting game that run on CGA and required a very slow CPU or cat reflexes - so I suppose there will be a few games that were pretty much hard-coded for XT era PCs and did't have (or need, back then) any delay loops. But those are rare. Then there's a bunch of games that would work on 286 systems but run too fast on cached 386DX40 - and it's not always obvious as the faster system does improve screen refresh rates, but also make the game way too hard or even unplayable. Same with 386 to 486DX2+ games, like Privateer, that "feel" better on faster systems but make the escort missions pretty much impossible to beat.

TL;DR: Any old game can ran too fast on a more modern systems, there is no rule.

Intel486dx33 wrote on 2020-02-07, 10:49:

But I ask do I need one ?

[...]

My 486 can run games intended for an IBM 5150 just fine.

Apparently, you have answered your question already. If even the oldest games you want to play all run fine on your 486, you don't need anything slower. But there are of course some games that will require an XT running at 4.77 MHz.

For as low as you can go. My parents' first computer, was a 286 8mhz, EGA gfx, 640k Ram and PC speaker.
It ran 3D Stunts, Stuntcar racer, Battle Chess, Sim City, Sim Life, Sim Earth, North And South, Commander Keen, Monkey Island and all sort of games like that just fine.

brostenen wrote on 2020-02-07, 15:45:

For as low as you can go. My parents' first computer, was a 286 8mhz, EGA gfx, 640k Ram and PC speaker.
It ran 3D Stunts, Stuntcar racer, Battle Chess, Sim City, Sim Life, Sim Earth, North And South, Commander Keen, Monkey Island and all sort of games like that just fine.

That’s what I want to know.
Can I build a PC to run at 4.77mhz or 8mhz? Or slower ?
How slow can a PC run at and still be able to play DOS games?
How does RAM and Cache have an effect on the CPU speed ?
What about system BUS ?

What would you recommend a 286 or 386 ?
What video card ?

You can even build a PC running with 1 MHz if you wish, since all early CPUs are simply driven by a quarz crystal. But what's the point? Wasn't your question if you need something slower? You don't, as long as the games you play all work as they should. The number of games that require XT-timing is very, very limited.

What games you want to play? There isn't a single system that can play all dos games. If you want to play alley cat, you could built 4.77Mhz one, but then you wouldn't be able to play newer games on that system that require instruction sets from 286 or 386. A 486 can be slowed down to play 286 or 386 speed sensitive games, so 286 or 386 are not absolutely necessary. If I just think about the games. I would most likely build a 4.77Mhz system and then jump to a 486.

Intel486dx33 wrote on 2020-02-07, 16:41:

That’s what I want to know. Can I build a PC to run at 4.77mhz or 8mhz? Or slower ? How slow can a PC run at and still be able t […]
Show full quote

brostenen wrote on 2020-02-07, 15:45:

For as low as you can go. My parents' first computer, was a 286 8mhz, EGA gfx, 640k Ram and PC speaker.
It ran 3D Stunts, Stuntcar racer, Battle Chess, Sim City, Sim Life, Sim Earth, North And South, Commander Keen, Monkey Island and all sort of games like that just fine.

That’s what I want to know.
Can I build a PC to run at 4.77mhz or 8mhz? Or slower ?
How slow can a PC run at and still be able to play DOS games?
How does RAM and Cache have an effect on the CPU speed ?
What about system BUS ?

What would you recommend a 286 or 386 ?
What video card ?

Sure you can build such a slow system. That would be an 8088 or 8086 system. However. That 286 my parents had, were in no way capeable of anything like Wolfenstein3D. It all depends on what games you want to play. Going for a 8086 at 4-something megaherz, will play Dos games, just not that many. If you wish to play games up to the first 3D games, doom excluded, you just need a 486dx33 with turbo button.

I run an IBM AT and a Pentium 90. Even with the AT at 6Mhz there are still some games that run too fast as they were meant for an 8088.

brostenen wrote on 2020-02-07, 19:38:

Intel486dx33 wrote on 2020-02-07, 16:41:

That’s what I want to know. Can I build a PC to run at 4.77mhz or 8mhz? Or slower ? How slow can a PC run at and still be able t […]
Show full quote

brostenen wrote on 2020-02-07, 15:45:

For as low as you can go. My parents' first computer, was a 286 8mhz, EGA gfx, 640k Ram and PC speaker.
It ran 3D Stunts, Stuntcar racer, Battle Chess, Sim City, Sim Life, Sim Earth, North And South, Commander Keen, Monkey Island and all sort of games like that just fine.

That’s what I want to know.
Can I build a PC to run at 4.77mhz or 8mhz? Or slower ?
How slow can a PC run at and still be able to play DOS games?
How does RAM and Cache have an effect on the CPU speed ?
What about system BUS ?

What would you recommend a 286 or 386 ?
What video card ?

Sure you can build such a slow system. That would be an 8088 or 8086 system. However. That 286 my parents had, were in no way capeable of anything like Wolfenstein3D. It all depends on what games you want to play. Going for a 8086 at 4-something megaherz, will play Dos games, just not that many. If you wish to play games up to the first 3D games, doom excluded, you just need a 486dx33 with turbo button.

Wolf3d ran on our 286/16 when it was sized down to a postage stamp.

gdjacobs wrote on 2020-02-09, 00:04:

brostenen wrote on 2020-02-07, 19:38:

Intel486dx33 wrote on 2020-02-07, 16:41:

That’s what I want to know. Can I build a PC to run at 4.77mhz or 8mhz? Or slower ? How slow can a PC run at and still be able t […]
Show full quote

That’s what I want to know.
Can I build a PC to run at 4.77mhz or 8mhz? Or slower ?
How slow can a PC run at and still be able to play DOS games?
How does RAM and Cache have an effect on the CPU speed ?
What about system BUS ?

What would you recommend a 286 or 386 ?
What video card ?

Sure you can build such a slow system. That would be an 8088 or 8086 system. However. That 286 my parents had, were in no way capeable of anything like Wolfenstein3D. It all depends on what games you want to play. Going for a 8086 at 4-something megaherz, will play Dos games, just not that many. If you wish to play games up to the first 3D games, doom excluded, you just need a 486dx33 with turbo button.

Wolf3d ran on our 286/16 when it was sized down to a postage stamp.

😁 yeah.... It is possible. However I was thinking full size and semi to full fluid.

brostenen wrote on 2020-02-09, 08:30:

😁 yeah.... It is possible. However I was thinking full size and semi to full fluid.

We could choose one of two.