As for the M725, I noticed that it does not differ much from the M729, in fact it looks like the same motherboard, with some different chips, but both the appearance and the main chips, seem to be the same, looking at my M725 motherboard, and the scrap board that I have, the latter seems to be actually an M729, on the back HW in the BIOS section, you can find in addition to the BIOS of the M729, some BIOS of origin M725, it is clear therefore that the differences are only in detail, and mainly in the renamed chips, here maybe they have simulated the output of a new motherboard, using renamed chipsets, The reality is that those chipsets are exactly the same as before.

Https://theretroweb.com/motherboards/s/ ... -m729#bios

However, to the human eye they will not have appeared, as a clear improvement, in fact they were very cheap cards, and in those years, the quality cost a lot. They were cards used on super cheap PCs, or for updates, the AT format was still ️ quite common, a similar motherboard, could represent a nice step forward, without having to change the entire PC, it was possible to reuse, VGA AGP RAM power supply, ISA or PCI cards, all things that added up cost more than the motherboard.
In the M725 I will initially use a VGA PCI, only later I will switch to a VGA AGP, but not only, I have to recover the Intel PII-300 CPU, which I still have on a Soyo SY-6BA+IV, which I should update to a P!!!-500, in short I will have to deal with several motherboards at the same time.

Today I worked on the Soyo SY-6BA+IV, first thing, I removed the 32 MB SDRAM, it is a PC66 module, not suitable for CPUs with FSB 100 or more, replacing it was easy, I took a 64 MB PC100, and I removed the 32 MB one.

For the moment I haven't decided how much RAM to put, but this card has four banks, so if you need it you can approach 1 GB, for the moment 64 MB is enough, later you may need other banks to install Windows.

Currently, there is a VGA AGP ATi Rage, for the moment it's fine, later I'll see to find something better, or adequate, for now the PC is quite limited, since I have a PII-300, so FSB 66 and multi 4.5X.

Unfortunately I can't find a PIII-500, I have a PII-400 that I tried, but it didn't work, I don't know why, and if that CPU works (?), to recover the PII-300, I temporarily use a Celeron 333 Slot1, we'll see later to try other Pentium FSB 100 CPUs, or I try a Slot1 370 adapter, and I try some Pentium S.370 with FSB 100 .

Running Phil's benches, I saw that the scores between PII-300 and Celeron 333 are very similar, some practically the same, a sign that the 33 MHz more, make no difference.

I continue with some tests, on the Soyo Slot1 (SY-6BA+IV), not having other Slot1 CPUs to try, I remember that I don't know the reason, but a couple of PII-400s don't work, while the Celeron 333 and the PII-300 instead do!

So I move on to an alternative, that is CPU S.370 and Slot1 adapter, I have one that I used many years ago on a PCCHIPS M741?, it's a Mendocino CPU adapter, I don't know which CPU is installed, maybe it's a 500, I don't want to remove the heatsink to check, anyway I tried to install this adapter, and it didn't work, but it could be great, a problem of inoptimal contacts, strange though that it doesn't happen with the two CPUs 300 and 333.

For the moment I would say, that the FSB 66 CPUs, have a good chance that they work, those with FSB 100, instead they don't seem to work, but having tried only two 400 CPUs, I don't know if the problem could be due to these, they should be tested on other MBs, just to see if they are working. ?!

In the CPU collection, I would have other adapters, for Coppermine CPU, I haven't tried any, but here probably, you could try, to put one with a PIII up to 1 GHz, or slightly lower, assuming that then the MB works, and starts correctly, at the moment only 300 or 333 MHz, it seems a bit little for this motherboard.

OHaving many pieces, in my collection, sometimes I don't find right away, what I'm looking for, I usually keep everything of the same type, in the same place, but it can happen that for different needs, something is moved, and after a long time ⏱, remembering where it is is not easy.

I'm looking for some Slot1 CPUs, among which there should be a PIII 133 FSB, a PIII 500 100 FSB, and maybe some others, I would like to try some CPU on the Soyo SY-6BA+IV, currently I have the Celeron 333, it works fine, but excluding overclocking, I would like to exploit it a little better, and be more above the half gigahz, then of course it depends on the CPU, but adapter or not adapter, at least I would like to get to FSB 100.

Among the adapters I have, there is an ASUS S370-DL REV 1.02, with Coppermine CPU, I don't remember if it's FSB 100 or 133, nor the frequency, I kept this adapter to use it on an ASUS Slot1 MB, because in the past I didn't have Slot1 CPU, initially I used adapter and S.370 CPU, in fact on my i810 M766LMRT2, to switch to PIII 1000/100, I used the adapter, because the MB's S.370 doesn't support Coppermine.

For curiosity and further info, here is enough:

Https://theretroweb.com/motherboards/s/ ... 6lmrt-v3-0

I try on the Soyo Slot1 (SY-6BA+IV), that Slot1 CPU that I didn't have between my legs, it was so evident, that I didn't notice it, it's one of the first Pentium!!! With FSB 133, as you can see, it is a 533B /512/133/2.0V SL3BN, given the voltage of the VCORE, it is not a Coppermine, these CPUs probably went on motherboards, with Intel i820 chipset, and although it is not officially supported, many put them on the 440BX or similar, those unfortunately i820 were problematic, for the use of RDRAM, some were adapted to normal SDRAM, because they cost much less, but there were other problems, with the additional chip for the conversion.

There is therefore the possibility that in this motherboard, it also works with FSB 133 (?), I don't know if from the manual this frequency was predicted, from the jumper present there are a couple of possibilities, open or closed, depending on the CPU used, however, there is to consider that at 133 of FSB, the AGP slot works beyond the factory frequency (66 MHz), so there could be some problem, with some video cards, which do not hold that frequency, currently I have a 4 MB ATI RAGE PRO TURBO, considering that the CPU is 300-333 MHz, it could be fine, but In the case of a CPU working at frequencies around 533-1000, a change may be necessary, with another more powerful card, remaining in ATI, a 7X00 or 9X00 are probably more than good, I am not very experienced in this regard, but this possible problem can be solved later.

For now, although I was quite confident, the CPU change didn't give any post code, I don't know what it depends on, mainly I think of the Slot1 contacts, because then putting the Celeron back, sometimes I have to remove it and re-insert it to see the post codes, so if there is no problem with FSB 100 or 133, it could only be some contact, which is a bit oxidized, I think it's better to clean the Slot1 and try the CPUs or adapters again.