A 486 would be the highest you'd want to go for games that old. A 386 would probably work just as well.

I used my 8MHz 286 until sometime between Wolfenstein (which wouldn't run full-screen at a good framerate) and Doom (which required at least a 386 due to 32-bit protected mode CPU code). My 33 MHz 386DX was so-so for Doom and TES:Arena (couldn't quite run at full screen with full quality) and poor for Descent.

Also, go for a 486 DX if you can, as the SX systems lack a math coprocessor I think and will be slower for some games.

As for connectors, expect to get the following on that generation of 486:
- AT keyboard connector (not PS/2)
- Serial port(s) for mouse and modem (PS/2 is possible but unlikely)
- Parallel port(s) for printer
- No USB (wasn't invented yet)
- 16-bit ISA slots for sound and SVGA video cards (and maybe one or two 8-bit slots as well)
- Possible VLB or PCI slot for faster video card and/or IDE controller, but probably not unless you get a late-generation 486 (e.g. 486 DX4)
- 40-pin IDE (PIO mode access only) for hard disks; modern CD-ROMs will probably be able to use this as well. Note that hard drives larger than 512MB might not work too well (even newer 486s can only handle a couple gigabyes max)
- Standard floppy interface (they haven't changed for at least 15 years)
- AT case and power supply (not ATX, which is standard now)

What you can use in the way of modern computer parts and accessories:
- Speakers (analog only, and anything more than stereo or 2.1 is probably a waste)
- Monitor with VGA input
- Floppy drive
- CD-ROM drive
- Parallel port printer
- PS/2 mouse with serial adapter

I'm sure you can find the parts on eBay. You might also try local thrift stores and garage sales (it's a long shot though).

Although an AT or 386 might be more appropriate for the older games, I can't recommend getting one, unless you find a working brand name unit with enough space for your drives and soundcard. Anything else might be too much trouble.
486 boxes and parts are easier to find, because more of them were manufactured, and many survived as Linux servers or doorstops 😁.
A standard ISA based 486 with 25 or 33 MHz would run 90% of the old games perfectly. You can disable the caches to get down to 386 speeds, and most machines have a turbo button, which is very effective with games that would otherwise run too fast.

HunterZ wrote:

Also, go for a 486 DX if you can, as the SX systems lack a math coprocessor I think and will be slower for some games.

You're right about the missing FPU, but I'm not aware of any games of that era using it. The only exception is Falcon 3.0 (see Trixters comment here).

Zork wrote:

Where would I be able to obtain such an old PC other than the greatness that is eBay?

If you don't want to use Ebay, keep your eyes open when visiting local flea markets or second hand stores. Asking your friends, relatives and workmates also might be a good idea. Often they know someone who wants to get rid of some old hardware.

To add to the discussion, let me suggest finding the most flexible 486 motherboard you can find... if you do choose the 486 route.

Two of my top choices (and there are other good ones) when I built my retro 486 were FIC's 486-PIO-3 and Asus's PCI/I-486SP3. Both of these had four ISA slots, 3 PCI slots, used newer 72pin FPM SIMM's, have onboard Floppy/HDD/Serial/Parallel controllers, and support every Socket4 processor from the first 486SX's/DX's to the last Pentium Overdrive and high speed processors from Cyrix (e.g. 5x86-120) and AMD (e.g. X5-133).

I found a 486-PIO-3 Mobo and use it almost everyday. I have a collection of working 486 processors, so I can swap CPU's if I think the game needs more or less horsepower. Ever see Quake run on a "486" with good framerate? Hehe. It can happen.

Except for a lack of VLB slots (which most can live without) these motherboards allow for a lot of flexibility. I've been completely satisfied with mine. Just finished replaying Star Wars: Dark Forces yesterday on it. 😁

QBiN: yeah that would be a later-model 486, which is faster than what Zork mentioned being interested in. I agree that it would give a lot of options though - I'm just not sure how well it would work with some older games due to the higher CPU speed.

Also, I had a VLB 486 mobo, and I used the slots for an SVGA video card and an IDE controller. You can get PCI versions of both of those (and they'll work better)

Just my opinions after i had to tear some such old piece of computers in pieces... The poor motherboard died.

Get a mobo. with at least one VLB slot for the video card. It will worth (or PCI of course if you can live with such). With VLB especially home - made games seem to work better written using the default graphic libraries of the programming languages (I mostly mean QBasic here).

If you can, get an LCD for the config. Most of the old games run in 320x200 at 70Hz, so they would not be a pain on CRT, but newer things written to the SVGA (or some rare pieces written to 640x480 VGA) will definitely stress the eyes on their 60Hz (For example WarCraft II can end up in a "painful" experience after a long play on CRT). Or get some set refresh application which can tweak up SVGA modes to run on higher rates.

For old computers, you will need NC, or somewhat similar, for newer ones you might want to install Win95/98 (If you have enough space to waste on the HDD :p ). In this latter case the more memory you have is the better - for EDO try to get for example four 16Mb modules.

By the way - usually - anything is OK to play DOS stuff on it dated before 2000. What i heard is that in later PCs there were less and less free UMBs finally ending up in that EMS memory could not be used at all, and of course drivers could not be loaded high, so more from the 640Kb was taken away making less games able to run. By the way from main memory on any such older PCs running DOS (or W95/98/ME) it is possible to make 620Kb free with a little of tweaking. On this amount anything will run.

The later 486 boards with PCI and integrated I/O are more comfortable to use (and I don't see much of a speed problem since you always can use a low-end 486 CPU in them), but they are quite hard to get and you may encounter strange compatibility issues: Early PCI chipsets usually are slower than their VLB counterparts and often have bugs in their PCI implementation. Also, they only support the PCI 2.0 standard, which means trouble for newer PCI 2.1/2.2 cards. Some versions of the integrated EIDE controllers (CMD640, RZ1000) need workarounds to run without errors. Building a high-end 486 is fun if you like messing around with hardware parts, but also requires more time and money than a standard low-end 486.
If you just want a trouble-free box for your old games, I'd suggest something on these lines:
- 486 SX/DX CPU with 25 or 33 MHz
- standard ISA-based motherboard (VLB optional)
- 4 to 16 MB RAM (30 or 72pin SIMMs)
- Tseng ET4000 VGA (1 MB DRAM, ISA or VLB)
- SoundBlaster 16 (non-PnP)
- standard HDD/FDD/I/O controller (ISA or VLB)
- any harddisk below 512MB
- ATAPI CDROM drive
- ethernet card (optional, useful for data transfer)
All these parts were very common in the 486 era and still can easily be found nowadays.

I really don't think it's necessary to have a VLB or PCI video card unless you're building a 66MHz or faster 486. The reason is that 25-33MHz isn't enough CPU power for most of the CD-ROM games that also required a VLB or PCI video card for hi-res FMV (full screen cutscenes). I only bought a VLB card for my 120MHz 486 because of games like Rebel Assault 2 (FMV, although I still couldn't quite run in hi-res) and Fade to Black (sound was choppy in movies with an ISA video card).

I just post my old config which one's mobo broke - until it worked it was really great:

CPU: 4.86 SX 25MHz (11MHz when TURBO was OFF)
Motherboard: It had ISA slots; three with VLB extension, no integrated IDE (The IDE controller was a VLB card)
8MB RAM (8x 1MB SIMM)
VGA: Cirrus Logic (I can not remember now the exact type), 512Kb video RAM, VLB - was awfully fast 😁
Sound: CMI8330 (Has nice - sounding FM 😀 )
HDD: 250Mb
Floppy: 5.25"; 3.5" (I have 5.25" floppies, so it is useful)
A weird CDROM, i think it's speed is 1x, but works nicely

The VLB video card is useful - especially if you wish to play around with some programming for example with QB or run such home - made games. When the mobo. broke i had to get a new one which i got with a P133 and a plain ISA VGA card. I tried to run my game which i programmed on that 4.86 on this new config (on the 4.86 it mostly ran at full speed), and it just crawled with somewhat around 4-6 FPS!!! :p The CPU was 5 times faster, and the game became 5 times slower! 🤣 - the old 4.86 could even beat this with TURBO turned OFF at 11MHz!

By the way as i studied the VGA spec, i found that it has many good features using which a 2D game can be greatly speeded up. So if a game relied on those actually the VGA hardware can do a lot of things - also needing lots of communication with the system. So there VLB is an advantage regardless to the CPU's speed. Now i try to code ASM, and find that with wisely using the VGA i might even be able to write a good izometric game to the original 4MHz PC since the VGA can do that much work that the CPU will really not have to do much more except transferring a few chunks of data and commanding the VGA hardware when rendering the graphic.