An external CGA monitor can be connected to the IBM PC 5155 and while it is true that these early games are playable in DOSBox on a modern computer, you don't get the same charm that one gets with real hardware.

Picking 486 as your PC #2 is fine choice. I was going to recommend 386, but it's such a personal decision that there's really no wrong decision. Everyone has different motivation for what to setup/keep/use. For me it's a combination of emotional attachment to something I had or something I always wanted. Your choice of IBM PC 5155, 486, P3, covers nicely different eras. I currently use primarily 386/33 and Dual PPro200. Bunch of other PCs are in a closet. If I wanted to be purely rational (while running on old HW), I would probably just use my single P4 machine which has ISA slots, can be clocked down to 286 level, multiboot and run smoothly virtually anything booting into DOS, Win98, WinXP.

It keeps coming up that the 5155 is rare and would be expensive to buy back. Which is only an issue, if it's actually being used instead of collecting dust. Having something to take up living space, just because it's rare and expensive without actually enriching your life is no strong argument. It only matters if it's hard to replace if you actually want to replace, it only matters if it's expensive, if you actually want to buy or sell it. If you already have it, all it costs is a volume of space. The question as well as the whole reason of this thread is, does it earn that cost? Though some people gain satisfaction just by owning something.

I think the one fix point everyone agrees on is keeping the P3-1000. Other than that it's what Tetrium said here. Rotate them for a couple of months to see which are the ones that you actually miss when aren't around and keep those.

AlexZ wrote on 2022-06-17, 16:42:

I would keep Pentium III 1000 and sell the rest. It can handle most of DOS games, some with disabled cache. Having 2nd machine would be justified in my opinion only if you wanted to play games on network. In that case I would have two almost identical machines so that no one would be in disadvantage. It also helps in case you need to troubleshoot instability issues.

Majority of DOS games should work fine with Pentium III, but I had some stability problems with couple of games (for example descent I and II crashed at startup) With 486 every game worked fine so far. Second problem is dont like these "soft" slowdown methods. Turbo button on 486 is just so much simpler and faster. Speed drops down to about 386DX33 level. Only issue i have with 486 is disk read problem that sometimes happens (Data error reading drive C: (Abort,Retry, Fail)

psychofox wrote on 2022-06-18, 17:28:

Majority of DOS games should work fine with Pentium III, but I had some stability problems with couple of games (for example descent I and II crashed at startup)

Certain DOS games that uses the DOS/4GW extender doesn't get along with more than 64MB RAM and there are two workarounds:

• Limit the amount of available RAM thru an utility like XMSDSK or HIMEMX.
• Use another compatible DOS extender such as DOS32/A.