1GHz celeron w/100MHz FSB is extremely likely to slap around a 750MHz PIII w/100MHz FSB for games. Having twice the cache will not save the PIII from the fact it's only running at 75% of the clock speed of the celeron.

Well, PIII has more cache with better 8-way associativity (vs 4-way on the celerons IIRC). However, for these older games, perhaps CPU speed matters more...especially with a Geforce 2 Ti I'll be running.

I thought I read on here that Coppermine celeron vs pentium was either 15% or 25% less performance for the celeron. So I figured it might be a close-ish match.

With Slot 1 it should be pretty easy to try both and check. That's one of a small number of reasons I do like the slotted form factor. Cooler comes away with the cpu, no need to fool around with coolers or thermal paste when you swap as long as both still have coolers.

Some months ago I tested a Celeron 1100 vs. Celeron 1000 vs. Pentium III 900 with Doom and Quake and the C1000 and P900 performed pretty similar:
Doom: 94.2 vs. 93.5 vs. 94.8 fps
Quake@320: 186.6 vs. 178.6 vs. 178.6 fps
Quake@640: 70.5 vs. 67.6 vs. 66.7 fps
(Geforce 5200 with FastVid)

So in your case I would use the Celeron

_tk wrote on 2023-01-19, 07:55:

Tried looking at old benchmarks and I can't really find many that compare the 100fsb celeron's to PIII's. Perhaps by '01 when the 100fsb Celeron's were being released people had already moved on. I see that Phil did a 1ghz Celeron video but he only compared to PIII's that were half the speed.

In the past I ran a number of 3DMark 99 benchmarks that included the 1000 and 1100 Celerons. In general the 1000 Celeron scores a tiny bit better than a P3 850. But as stated above, it is possible that the larger cache of the P3 results in better scores in certain games. Depending on the videocard I would choose to run a P3 800 or 850 in order to not stress the VRM of the motherboard too much - those high end Celerons draw a lot of power. Here an overview that gives some impression:

Would running at 112 MHz FSB be an option? Should only overclock AGP slightly ...

PARKE wrote on 2023-01-19, 14:16:

Depending on the videocard I would choose to run a P3 800 or 850 in order to not stress the VRM of the motherboard too much - those high end Celerons draw a lot of power.

Maybe not use the board at all, then it will not wear at all too, no? 😉 Sorry I couldn't resist.
I have yet to see a BX board that has problems running any of the Slot1/soc370 CPU's supply power-wise. There were some problems with early LX board (mostly AGP 3.3v supply and maybe some had weaker MOSFET's) but over 25 years having messed with tens (or perhaps hundreds) of BX boards they all work nicely with whatever CPU you decide to use there. Even one of my favourite builds back in 2002 using Gigabyta GA-6ZMA (mATX with ZX chipset and onboard Ess Solo1 audio) worked like a champ with cherry picked Celeron Tualatin 1300 @ 1733 (at 1.6v). It was my main gaming rig paired with Ti4200 and 2x256 RAM.

I did a comparison of Celeron and PIII and PIII ended up being totally superior:

3D Mark 99 (1024x768 32bit, FX5600)

• Celeron 1000 - 5534
• Celeron 950 - 5441
• PIII 900 - 6190
• PIII 750 - 5682

3D Mark 2000 (1024x768 32bit, FX5600)

• Celeron 1000 - 4076
• Celeron 950 - 3940
• PIII 900 - 5805
• PIII 750 - 5348

3D Mark 2001 (1024x768 32bit, FX5600)

• Celeron 1000 - 4774
• Celeron 950 - 4730
• PIII 900 - 5512
• PIII 750 - 4665

Celeron has 1/2 cache and lower cache associativity which hurts it badly in games.

The conclusion is Celeron 1000 is about equal to PIII 750 but at 1/4 higher energy consumption and more heat. You may be putting extra strain on old motherboards for no gain. If you want a very fast 100Mhz FSB PIII then get PIII 900 with slotket. If your board is stable at 133Mhz FSB (only late boards with 1x ISA, FSB usually goes to 150) then get PIII 1Ghz. I ended up getting a PIII 900 and it is sufficient up to year 2002 games.

Fascinating. Interesting that the FSB bottleneck at high mult is significant enough that the cache reduction makes that big a difference.

Appreciate the 3D mark scores. That was about the consensus that I had read but good to have it confirmed. That's why I thought the 1ghz celeron vs an underclocked PIII 1ghz (@ 750mhz) might be about equal.

However, I took a look and the TDP on the Celeron 1ghz is 29W. For the 1ghz Pentium III it's 29W. as well .

They seem to be about the same Celeron vs Pentium III when comparing ghz and the Coppermine cores. How is the Celeron drawing more power and running hotter than its P III mhz equivalent?

_tk wrote on 2023-01-20, 23:04:

They seem to be about the same Celeron vs Pentium III when comparing ghz and the Coppermine cores. How is the Celeron drawing more power and running hotter than its P III mhz equivalent?

the voltage that's printed on the CPU differs by sspec/stepping, and is the minimum voltage that the bios will let you set. afaik after that 1.13ghz fiasco, the steppings that intel put out are specified at 1.75v, at least down to the piii 700. so that one could be running at 1.65v or 1.75v depending on sspec...

Celerons are very energy inefficient for the performance they offer and given availability of PIII are a poor choice for anything else than testing unknown boards. They will run hotter because you need much higher frequency and TDP for the same performance. The performance penalty is huge at high multipliers. PIII 900E pays it as well but gets saved by cache. In 3d mark 99,2000,2001 PIII 900E is about as fast as PIII 840 (7.5x112) or PIII 800 (6x133).

_tk wrote on 2023-01-20, 23:04:

They seem to be about the same Celeron vs Pentium III when comparing ghz and the Coppermine cores. How is the Celeron drawing more power and running hotter than its P III mhz equivalent?

P3 and Celeron of the same frequency draw the same power.
The only reason I can see to use a high end Celeron instead of a P3 occurs when you cannot score a P3 that is powerful enough. And that also depends on the videocard that you use. For example: a Voodoo 3 runs at its maximum speed on a P3 with frequency of approximately 800 MHz and in such scenarios there is no need for a faster cpu.

I went with a Celeron 1100 in a slotket for my 440bx board just because the 100MHZ FSB P3 chips are being stupid prices in excess of $100 on ebay. If you even find one. I hate to go e up the performance but financially it made more sense

9646gt wrote on 2023-01-22, 08:42:

I went with a Celeron 1100 in a slotket for my 440bx board just because the 100MHZ FSB P3 chips are being stupid prices in excess of $100 on ebay. If you even find one. I hate to go e up the performance but financially it made more sense

Yeah, they are ridiculously expensive for some reason (100mhz fsb P3's). Rarity perhaps and guys with BX boards doing what I'm doing?

I tried my 1100mhz Celeron on a CUSL2 and it works fine. For one reason or another, my P3B and/or Asus slocket won't boot with it.

_tk wrote on 2023-01-25, 21:58:

9646gt wrote on 2023-01-22, 08:42:

I went with a Celeron 1100 in a slotket for my 440bx board just because the 100MHZ FSB P3 chips are being stupid prices in excess of $100 on ebay. If you even find one. I hate to go e up the performance but financially it made more sense

Yeah, they are ridiculously expensive for some reason (100mhz fsb P3's). Rarity perhaps and guys with BX boards doing what I'm doing?

I tried my 1100mhz Celeron on a CUSL2 and it works fine. For one reason or another, my P3B and/or Asus slocket won't boot with it.

I reckon this is about into the right direction.

Due to following this thread, I couldn't help myself when I found a Coppermine P!!! 1100 on a Danish buy/sell page, maybe US$45 was a bit over the top, but on the bright side I now have 2 of them ... And an Asus P2B-DS: D

A Pentium III SL5QW - Coppermine - 1100/256/100/1,75V is the best native setup for ASUS P2B-DS. Congratulations!

Very nice machine! What kind of slotket are you using?

I am slowly collecting parts with the intention to build a relatively "fast" 98SE machine based around an Asus P2B-F and GF3 Ti 500 (which I already have). I was hoping to find a higher clocked 100MHz FSB Slot 1 Coppermine for it, but the unavailability / high price of those CPUs may not make that feasible. Therefore, I'm possibly considering a S370 Coppermine with a slotket as an alternative.