Gmlb256 wrote on 2023-10-26, 19:16:

Jasin Natael wrote on 2023-10-26, 16:44:

The chip i've got clocks pretty decently, I was able to run it at 1600 (12x133) and pass all benchmarks and a 1+ Unreal flyby with no crashing or artifacts.

Lucky you! 😁

Mine required a very small core voltage bump just to get it stable at 1.46 GHz.

Yeah I was pleased. I usually don't get lucky with the silicon lottery.

Socket3 wrote on 2023-10-26, 14:49:

Out of the box, no i440 board is compatible with the VIA C3. Some models (Abit BE6, BH6, BX6 to name a few) are compatible with the C3 Samuel core with the latest bios, but performance and stability are a mixed bag.

VIA C3 chips are designed to work with VIA chipsets. Specifically, the Ezra core C3 is designed for the VIA 82C694X while the Nemiah is technically designed to work with the VIA 82C694T chipset, but it will also work ok in some i810 and some i815 boards (Abit ST6 for example).

You write it like there are design documents about such compatibility, that point out what makes or breaks it. There are the C3 PDF Datasheets, The only BIOS writer's guide I found is for cancelled Joshua C3. Often the actual result with a C3 + Motherboard is just an observation, without proper explanation.

When I was first tinkering with VIA C3s, I had to label Samuel, Samuel 2, Ezra and Ezra-T as partially defective chips, as in: too slow in cache and memory throughput. Nehemiah appeared to behave as advertised. And that was on a i440BX motherboard, with a VIA Apollo Pro motherboard on the side, to verify things. Maybe VIA wasn't quite finished with the processor design, but released them anyways. They had their Cyrix-based Joshua C3 failure at first, they had trouble getting Nehemiah ready and therefor pushed Ezra-T.
VIA C3 is a continuation of the IDT Winchip design by Centaur Technology. So it is not all VIA here. If VIA had designed a x86 CPU from scratch, it would probably be way worse.

But the good thing about retro computing is that you can verify and benchmark any build combination, so in the end anyone can find out what is of practical use for them: If a certain slowness is a problem or a feature, and whether or not reliability is sufficient. Then decide if the different speed settings are useful, or unnecessary.
VIA C3 is the opposite of "maxing-out" a build. Instead of trying to squeeze more out of a 486, Pentium 54/55C or K6 system, you take a Slot-1 or Socket 370 system and slow it down. Surely there are many retro-computer hobbyists who don't find that an appealing concept.
For 3D DOS games in hi-res it is beneficial to enable MTRR Write Combining + fast FSB + preferably AGP interface. As supported by K6-2 CXT+, Pentium II/III+ and VIA C3. Earlier processors miss out on this.