When I started going through my retro stuff, first thing I did was get a stable 440BX system for parts testing Gateway E-4200 because I was going crazy trying to piece together a mismatch of 1/2failing parts. I found the 440BX to be a very compatible chipset with support for a wide variety of hardware from different time periods. I just wish gateway 's ftp site had not gone down the toilet.

If the P2B-F motherboard is stable, I think it's a very good choice, because its got ISA, PCI, and early AGP, ASUS still offers downloads for the board and the latest BIOS supports 266 - 800Mhz CPUs.

I have a similar build and it works ok for DOS gaming. You won't get super high frame rates while playing Quake and Tomb Raider at 640x480 but otherwise, it's a solid choice.

You can also use ACPI Throttle for more slowdown options, if you need to go to 486 or early Pentium levels.

appiah4 wrote on 2020-12-19, 14:00:

I am throwing together a Slot 1 PC to be primarily used as a test bed for ISA/PCI/AGP(2x) cards. I also plan to do DOS gaming on it. The motherboard is a P2B-F. Would a Celeron 400 be a good fit? As far as I can tell it slows down to 386SX25 speeds with L1 disabled which is perfect for me.

Do you have any other slot 1 cpus to try out? There are several DOS games that could use all the cpu they can get if you want smooth 640x480 performance. I'd say 600-800Mhz would be a good max. I'm just not sure how those cpus will slow down compared to your Celeron 400.

It'will be fine.

clueless1 wrote on 2020-12-19, 14:51:

appiah4 wrote on 2020-12-19, 14:00:

I am throwing together a Slot 1 PC to be primarily used as a test bed for ISA/PCI/AGP(2x) cards. I also plan to do DOS gaming on it. The motherboard is a P2B-F. Would a Celeron 400 be a good fit? As far as I can tell it slows down to 386SX25 speeds with L1 disabled which is perfect for me.

Do you have any other slot 1 cpus to try out? There are several DOS games that could use all the cpu they can get if you want smooth 640x480 performance. I'd say 600-800Mhz would be a good max. I'm just not sure how those cpus will slow down compared to your Celeron 400.

Well, yeah. With regards to Katmai and Coppermine I have the following in Slot-1 form:

Pentium II 333 Deschutes (In my XPS D333)
Pentium II 350 Deschutes
Pentium III 450 Katmai (fan needs servicing)
Pentium III 500 Katmai (In my 1996-1998 PC)
Pentium III 55o Coppermine
Pentium III 600 Katmai
Pentium III 700 Coppermine

I also have the following Socket 370 CPUs I can use in a slotket:

Celeron 533 Mendocino (I have two of these I hope to use in a dual Socket 370 motherboard some day.. Not that I've been able to get one yet.)
Celeron 900 Coppermine
Pentium III 700 Coppermine (100MHz FSB)
Pentium III 850 Coppermine (100MHz FSB)
Pentium III 1000 Coppermine (100MHz FSB)

I picked on the Celeron 400 because it is the slowest, I thought faster stuff would be problematic on the low end. A Celeron 400 + 64MB Ram would probably run just about anything? The only games I foresee being a pain in the ass would be those that crash on 200MHz+, and games that target specific 486 speeds (Ultima VII, Theme Park.. are there any others?)

Finally, I have a Chaintech CT-AJA4T Socket 370 VIA Apollo Pro 133T motherboard in the mail that would open up all the options including 133MHz Coppermines and Tualatins but I'm not sure those have any business in a primarily DOS and testing build. Also, VIA wouldn't be my first choice for this thing regardless, 440BX is a much more stable chipset to test things on. So based on the above, which would you go for?

Slot 1 / socket 370 is generally not suitable for DOS gaming, but, as always, it really depends on what games you want to play.
I just finished messing around with a Slot 1 Celeron Mendocino 300A (overclocked to 450 MHz) on an EPOX EP-BX3 (Intel 440BX) motherboard. A very decent CPU in Windows 98, comparable to a K6-2+ overclocked @ 616MHz (but faster in raw FPU).
In DOS it's also very fast, and it's even faster in Quake and other late era DOS games when enabling write combining with FASTVID. However, with a disabled L1 cache I only get 8 FPS in 3DBench 1.0c (as you said, comparable to a 386SX-25). This level of performance does not cut it for me... It's way too slow for the speed sensitive games that I play. For example, Titus the Fox is speed sensitive when it comes to sound - past a certain CPU speed (usually 486 DX2-66 is already too much), it defaults to PC speaker sounds. So the ideal CPU for this game is a 486DX-33 (19-20 FPS in 3DBench 1.0c). A 386SX-25 is way too slow... the game will be a stuttery mess.
I then replaced the Celeron with a Pentium 3 Coppermine @ 933 MHz and this one fares better with a disabled L1 cache (15 FPS in 3DBench 1.0c), but still not ideal. Also, 486/early Pentium speeds are out of the question...

My advice for a fuss-free / no compromises early-mid (and a bit of late) era DOS gaming PC would be a Pentium MMX 200/233 MHz & 430TX PC - It. Just. Works.
Another option is Super Socket 7 with a K6-2/3+ CPU, but this platform is definitely not fuss-free (some motherboards just work perfectly, others... not so much).

I've become very partial to the Via C3 Nehemiah. But good luck finding one for a decent price. I lucked out some years ago and got 4 of them for an unbelievably low price.

The games that are most demanding in 640x480 are Duke3D/Shadow Warrior/Blood, Screamer 1/2, US Navy Fighters (up to 1024x768), System Shock, CyberMage, Links LS (up to 1600x1200), and Quake. There are probably others, but those are the ones I'm familiar with. I'd pick some of those to test with, then have a few games that need slowdown (like Wing Commander) to check how those cpus do when L1 is disabled. I'm guessing the 600Mhz Katmai will be a good choice.

I'd be curious how performance compares between Katmai and Coppermine at the same frequency with L1 disabled. 😎 I'm guessing Coppermine would slow down more (maybe too much more).

If you're good with overclocking, a 333 or 366 Celeron is often good for 500 or 550 MHz on a BX board. I ran dual 366's@550 back in the day ..
So, higher max, lower minimum clock ..?