Has anyone tried this combo?

2 of the above 440LX + Slocket with a socket 370 Celeron on a Shuttle brand board with great official BIOS support .
From what I've seen , the P2L97-DS seems to be more limited : https://www.asus.com/supportonly/P2L97-DS/HelpDesk_CPU/ .
According to https://translate.google.ca/translate?hl=en&s … 577&prev=search , with a recent (latest?) BIOS, Coppermine Pentium 3 based Celerons (and most likely Coppermine Pentium 3 CPUs too ) should at least POST . Cyrix CPUs, I do not know .

I did try a Slot 1 P3 (500 IIRC) in it but it wouldn't post. Not sure if it's incompatible or just a bad CPU.

If the BIOS is sufficiently updated, I would expect it to at least POST, as that is a Katmai core, which is older than Coppermine and Coppermine apparently works (see above).

I have a Cyrix III 700 (7x100) or a PIII/600 (6x100) that I could use. Are either of these chips likely to work with the 440LX mobo?

I have never tried, but if I had to guess I would say no (fairly uneducated guess). Additionally, the voltage requirements of these CPUs are likely incompatible with your board's VRM . Unless any of these can safely run at 2V (maybe 1.8V if this is accurate http://baber.com/baber/411/asusp2l97ds.htm ), you risk CPU damage

Also are there different types of slockets I have to watch out for, or are they all functionally the same?

Chronologically :
a) PPGA capable, the oldest type, that only supports first generation socket 370 CPUs . May or not have jumpers for FSB and VID voltage (to force the motherboard to supply a given voltage, if it is capable)
b)FC-PGA capable that supports Coppermine CPUs . May or not have jumpers for FSB and VID voltage (to force the motherboard to supply a given voltage, if it is capable)
c) FC-PGA2 capable that supports Tualatin CPUs . Usually has jumpers for FSB and VID voltage (to force the motherboard to supply a given voltage, if it is capable). At least one series from Powerleap has an onboard voltage regulator to allow bypassing the limits of the motherboard VRM .

Slocket types b) and c) will usually work with older CPU type through the use of jumpers or DIP switches . Generally, the motherboard BIOS must recognize at least the CPU family for the system to POST .

Thanks for the detailed rundown - minor correction, my board is actually a P2L97-S and not a DS (the DS is the one I actually want, guess I had it on the brain when I wrote the first post. 😜 ) Anyway the S lists support for a few more CPUs and also apparently has the 1.8V voltage regulator according to the other site.

When did they change cores in the 66FSB Celerons? If this board can run a 433 it should be able to run something higher, right?

Thanks for the detailed rundown

You're welcome .

When did they change cores in the 66FSB Celerons?

533MHz is the cutoff point . The 533MHz Celeron exists in both a PPGA variant (Mendocino, same as the 433MHz) and a FC-PGA variant (Coppermine) known as 533A .
See http://www.cpu-world.com/CPUs/Celeron/index.html for more info one variants.

If this board can run a 433 it should be able to run something higher, right?

At least up to 533MHz PPGA (Mendocino) SL3FZ S-spec (unless you want an engineering sample), I would guess .

Somebody seems to have had some luck with the plain variant of the P2L97 (non SCSI) and a 766 MHz Celeron (Coppermine) by setting a jumper-equipped slocket to 1.8V (technically slightly overvolting the CPU whose stock voltage is between 1.65 and 1.75V, depending on actual unit) :
http://www.tomshardware.com/forum/152422-30-p … 97-celeron-s370

Based on my experience of a VIA C3 800MHz CPU, would a 700MHz Cyrix III be much of an upgrade over the PII?

Not sure it will work - would depend on BIOS support I imagine. I remember trying my C3 in an SIS Chipset s370 motherboard and that didn't work, but a P3 Tualatin did. Had to get a VIA board for the C3 in the end - purpose of that system was for a passively cooled fanless server.

Well, I got it to boot with a different P3, a 550/2.0V. This gives me a solid 366MHz @ 66 FSB or a delightfully odd 412.5MHz @ 75. That puts me right into the 400~600MHz sweet spot I was shooting for. I'll mess with a slocket if I need more speed later.

Not sure what was wrong with the P3/500, if anything. I did have to take this one out and insert it a couple times to get it to seat properly as it was REALLY tight against the retainer clip. Maybe that was the issue the first time.

Incidentally I took this P3 from a Dell XPS, which has a sort of shroud that blows air directly down on it from the rear case fan, so it's passively cooled for now. Not sure if I can get away with this despite it being underclocked; I might have to swap on the active HSF setup from the other one. I was also thinking to put heat sinks on the north & southbridges with some arcitc silver. What do you guys think?

Does the P2L97 let you adjust Vcore? If it does, try undervolting it.
The voltage regulator IC on a P2 board should at least support down to 1.8V.