I would probably suggest this approach:
1) Look at the supported CPU list for that motherboard (if there is one...), and sort from fastest (highest clock rate) to slowest, and
2) Look at the prices for those CPUs in your area until you find some that fits within your budget

What was the fastest 100MHz FSB PIII in slot 1? According to Wikipedia, the 1GHz. I... suspect... the 1GHz is going to be relatively pricy (slot 1 stuff generally tends to be, plus 1GHz has that psychological 1GHz thing), so... go down two notches and see what the pricing on, say, the 800 or 850 is like?

Pentium II 450 or Celeron 300A @450. 👍

AlessandroB wrote on 2023-10-29, 21:40:

In the middle if my socket 7 and Pentium 4 i have a nice slot1 IBM 300GL, accept SLot1 CPU Bus 100Mhz, Tualatin i think is not supported. Wich cpu i choose? The Fastest PentiumII in classic SECC1 (Like 450Mhz) or a Middle PentiumIII (Like 600Mhz) or something fast, like 800Mhz? And Why??? Thank for your interesting suggestion.

When I look up IBM 300GL, I get a Socket 7 mobo? (https://theretroweb.com/motherboards/s/ibm-pc … 272,-6282,-6284)

Can you give us more information? Am I looking this up wrong?

kingcake wrote on 2023-10-29, 23:30:

AlessandroB wrote on 2023-10-29, 21:40:

In the middle if my socket 7 and Pentium 4 i have a nice slot1 IBM 300GL, accept SLot1 CPU Bus 100Mhz, Tualatin i think is not supported. Wich cpu i choose? The Fastest PentiumII in classic SECC1 (Like 450Mhz) or a Middle PentiumIII (Like 600Mhz) or something fast, like 800Mhz? And Why??? Thank for your interesting suggestion.

When I look up IBM 300GL, I get a Socket 7 mobo? (https://theretroweb.com/motherboards/s/ibm-pc … 272,-6282,-6284)

Can you give us more information? Am I looking this up wrong?

Exhist also a PMMX version. IBM 300GL o 300PL are basically the same, support all PentiumII and PentiumIII up to 800 because was the fastest at the time of production.

It depends on what multipliers the board supports as to what cpu you can use on it.

Piii 600e might be a nice middle ground but so would a 700 or 800. But they will cost more.
Shame it's not a 133 bus, I have a couple 600eb's going spare.

ubiq wrote on 2023-10-29, 23:29:

Pentium II 450 or Celeron 300A @450. 👍

Pentium II 300 SL2W8 or SL2YK. I have like 5 of them., all of them working @450.
Mine 300GL supports only 2.0V Pentiums III.

Problem with >800 MHz P3's is bios support. Apparently, there's a microcode update which all boards didn't get ..

VivienM wrote on 2023-10-29, 22:50:

I would probably suggest this approach: 1) Look at the supported CPU list for that motherboard (if there is one...), and sort fr […]
Show full quote

I would probably suggest this approach:
1) Look at the supported CPU list for that motherboard (if there is one...), and sort from fastest (highest clock rate) to slowest, and
2) Look at the prices for those CPUs in your area until you find some that fits within your budget

What was the fastest 100MHz FSB PIII in slot 1? According to Wikipedia, the 1GHz. I... suspect... the 1GHz is going to be relatively pricy (slot 1 stuff generally tends to be, plus 1GHz has that psychological 1GHz thing), so... go down two notches and see what the pricing on, say, the 800 or 850 is like?

For some reason (maybe a lot wasn't made) the 800 and 850 slot1 100FSB are stupidily expensive. Probably the 1GHz/100MHz as well ..

H3nrik V! wrote on 2023-10-30, 10:55:

VivienM wrote on 2023-10-29, 22:50:

I would probably suggest this approach: 1) Look at the supported CPU list for that motherboard (if there is one...), and sort fr […]
Show full quote

I would probably suggest this approach:
1) Look at the supported CPU list for that motherboard (if there is one...), and sort from fastest (highest clock rate) to slowest, and
2) Look at the prices for those CPUs in your area until you find some that fits within your budget

What was the fastest 100MHz FSB PIII in slot 1? According to Wikipedia, the 1GHz. I... suspect... the 1GHz is going to be relatively pricy (slot 1 stuff generally tends to be, plus 1GHz has that psychological 1GHz thing), so... go down two notches and see what the pricing on, say, the 800 or 850 is like?

For some reason (maybe a lot wasn't made) the 800 and 850 slot1 100FSB are stupidily expensive. Probably the 1GHz/100MHz as well ..

The 1GHz 100FSB would certainly have been relatively rare because the i815 and socket 370/133 FSB came out a few months later. So most large OEM 1GHz systems were probably i815 370s.

But the 800/850... I don't know. The question is how much more money they were, and how long they were on the market.

I will note that this is starting to be around the time of the Celeron launch, etc. A couple of years earlier, you had chips like, say, the Pentium 166 that launched as high-end, then gradually fell down in price as newer higher-end options were launched. By this point, Intel doesn't intend to offer the PIII 850 as a low-priced option in 2002; in 2002, the 850 is long gone and they have a nice Willamette Celeron for you...

Also, there's the AMD factor. My recollection is that this happened to be a time when the first Athlons were very popular and much more affordable. So... probably fewer slot 1 CPUs in enthusiast systems that are more likely to be stripped down for parts, and more slot 1 CPUs in businessy/etc systems that often go straight to e-waste.

That being said, I wonder if this is just reflecting a lot of demand. The slot 1 440BX systems have always been well-regarded, maybe there's just always been a lot of demand from people continuously wanting to upgrade lower-speed slot 1s to higher speed slot 1s, both in the ~2003-4 era when you'd expect the value of these processors used to have plunged and continuing to this day.

There were a metric ton of P3 800EBs. In mid/late 2000, the OEMs were pumping out a ton of Slot 1 800EB+Apollo Pro 133A systems, as they were in the pricing sweet spot.

800Es? Probably not a lot.

I not think i need the fastest one because the P4, what you think???

Slotket + PIII 900E.

A long time ago (maybe 15 years?) I bought a bulk lot of Slot-1 CPUs. Among them was one P3-850E. It was the best CPU in the lot but they were going for $50 on eBay at the time so I sold it. So even back then they weren't easy to come by, I imagine they're a lot harder to get now. I never saw a 1GHz/100 at all, I've only seen their existence on the Intel site which *used* to have a conveniently searchable database of all their CPUs.

For most Coppermines above like 700MHz, a slocket is the only way to keep the cost down. But I haven't shopped for a slocket recently, I guess those are probably getting expensive too.

Alot of P2 era boards max out with a P3 600 Katmai due change of VRM requirement.
Apart from that for this era not a lot of benefit of going slower instead of faster. so would go with the fastest budget and availability allows

Much like the 486 DX2/66 for a long time games minimum system requirement were a PII 400 so I guess you could go with a defacto PC spec, not my idea of fun though

Yes lots good suggestions I would go with a 500 or 600mhz slot unless you already have a board that supports a 700-800 P3.... just a thought.

shamino wrote on 2023-10-31, 22:59:

I never saw a 1GHz/100 at all, I've only seen their existence on the Intel site which *used* to have a conveniently searchable database of all their CPUs.

They do exist - I have one, I got from some scrap lot ... will post an image later - can't get that to work from my phone for some reason ...

I have checked, i already have a PIII 500 Slot1. I have to look for something faster on ebay…

Since is my “the fastest” ISA-DOS machine (P4 i think will be windows/only) PIII 500 will be fast enough or i spend money for somerhing like PIII 800?

Hopefully the right picture with some evidence that 1000/100 exists 😀

H3nrik V! wrote on 2023-11-01, 15:55:

Hopefully the right picture with some evidence that 1000/100 exists 😀

SECC1 is much nicer….