. At least with the SS7 platforms you can have an all-in-one PC, one that is capable of successfully running most DOS games, Windows 95 and early Windows 98 games.

You can achieve that with VIA C3 or P2 Klamath on Slot 1/Socket 370 system. And realistically, throttle via ACPI should be sufficient enough, for the most part.

I have tried to use ACPI throttle on many 440BX boards and I've had very bad results with it (anything above a 30% throttle causes an abnormal gameplay stuttering - even though when testing with 3DBench framerates are still high). The issue seems to be linked to sound - which is handled by the throttled south bridge (even though I tried many cards, both ISA and PCI). Anyway, VIA chipsets are much better for this, so I'm sticking with them for ACPI throttling.
The Klamath is hot, hard to overclock and slower than a K6-2/3+ (so might as well just go with the latter)...
There are some Deschutes which are unlocked too, can be easily overclocked/underclocked, but they are harder to find.

Made some more Tests

384Mb RAM on HOT591:

128Mb RAM on HOT591:

Look at CPU Marks, as you can see a K6-2+ does not fully solve Cacheable Issues.

Also visible in Quake 3 Max/Min Frames, if going over Cacheable Area there some weird Framedrops.