I don't think it matters much which of those 2 CPU's you pick. I'd say just pick the one you happen to have available and if you have both, just pick the one closest to your hands after opening your box of Slot 1 CPU's 😜

Edit: On second thought, the P2-450 does have a "coolness" factor that the slowest Katmai is lacking. If it matters anything to you, I'd say go with the Deschutes 😁

Yep, I am thinking I'll go with a Deschutes too.

I'm trying to replicate the system I was running back in 1998. Well, I'm getting as close to it as possible.

Back then, I ran a Celeron 300A at 450mhz because I was too broke and/or cheap to pay for a real P2 450. Now that I have actual money and P2 CPUs are cheap, I'm thinking I'll go with the real P2 450 Deschutes.

It looks like the only major difference between the Deschutes and Katmai is the SSE instruction set. Does SSE have an impact on any games?

From Redhill hardware:

Pentium II 450 and Pentium-III 450 The Pentium II 450 had one of the longer reigns as the world's fastest X86. Until the arrival […]
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Pentium II 450 and Pentium-III 450
The Pentium II 450 had one of the longer reigns as the world's fastest X86. Until the arrival of the K6-III/400 and then the Pentium-III 500 in March 1999, only an Alpha was faster. As always with top of the line parts, the price-performance ratio was dreadful though. Even by winter '99, at the end of their market life, they remained poor value and continued to sell in tiny numbers only. We can't have seen more than two or three.
You'd never have known it from the media hype, but only three things distinguished the Pentium II and this original Pentium-III: a revised production process, the Streaming SIMD (SSE) multi-media instructions, and the biggest advertising campaign the industry had ever seen. In all other respects the two chips were exactly the same, and the Pentium-III offered no performance gain over the Pentium II.
It was, in short, a smoke and mirrors upgrade, offering a massive publicity push instead of actual performance improvements. With the Merced project running late and slow, and the AMD Athlon about to hit, Intel pulled off an old showbiz trick: when you forget your lines, smile and concentrate on looking confident — if you sound upbeat enough, no one will notice that you've fluffed it.
At first, of course, they were absurdly expensive. By mid-winter '99 though, they were semi-reasonable: only about 30% more than an equal-performance K6-III/400 or Celeron 500.

So the pII 450 is that scarce? I have two in a tyan thunder board actually.

JaNoZ wrote:

So the pII 450 is that scarce? I have two in a tyan thunder board actually.

It's definitely more uncommon then the 450 Katmai, that's for sure 😜

KT7AGuy wrote:

Yep, I am thinking I'll go with a Deschutes too. […]
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Yep, I am thinking I'll go with a Deschutes too.

I'm trying to replicate the system I was running back in 1998. Well, I'm getting as close to it as possible.

Back then, I ran a Celeron 300A at 450mhz because I was too broke and/or cheap to pay for a real P2 450. Now that I have actual money and P2 CPUs are cheap, I'm thinking I'll go with the real P2 450 Deschutes.

It looks like the only major difference between the Deschutes and Katmai is the SSE instruction set. Does SSE have an impact on any games?

You do know that the cache on a 300A runs at full speed while it runs at only half speed on a P2, right? That might make a big difference in overall system performance if you overclocked it to 450 instead of getting a real P2.

sliderider wrote:

You do know that the cache on a 300A runs at full speed while it runs at only half speed on a P2, right? That might make a big difference in overall system performance if you overclocked it to 450 instead of getting a real P2.

The reason I no longer have my original Celeron 300A system is because it fried. I don't know if it was due to the overclocking, but it makes me hesitant to do it again. Celeron 300A CPUs aren't cheap on eBay. I'd hate to fry another one.

Even though the Celeron 300A's cache runs at full speed, it only has 128K of it. Wouldn't the 512K cache and 100mhz FSB of the Deschutes or Katmai compensate for that?

If you run Celeron 300A @ 450 then you also have FSB @ 100MHz. Benchmarks usually showed C@450 abit faster then a P-II 450.

Some reviews from back then:
http://www.tomshardware.com/reviews/big-cpu-shoot,84.html
http://www.anandtech.com/show/174/4

I bought a dual PII-400 Dell Workstation Nov/Dec. 1998 and recall the price difference between the PII-400 and PII-450 being absurbly high. As such, I suspect most buyers, like me, went with the PII-400 over the PII-450. And the PIII-450 was right around the corner. Those were exciting times - never to be repeated, I suspect.

I have to vouch for the PII 450 though, it's an amazing processor. I switched my PII 300 up to one a while ago and it flies, it actually outstrips my Athlon 1500+ in Build Engine games - though that could be because of the Matrox Productivia seemingly being faster in those video modes than the GeForce 4.

Another option is to get a pentium 2 300mhz and set the fsb to 100 so it will work at 450mhz.

I kinda like the PIII 450. The hot stepping was SL35D which has cache chips of the PIII 600. That means you can often get to 600MHz or more. I upgraded from a PII 300 SL2W8 which itself was essentially a PII 450 in disguise. I ran that at 504MHz on a Abit BH6.

I never bothered with any Celeron. I think I was offset the times of the Celeron popularity windows a little bit or something.

In other words if you are hell bent on a PII 450, you could get a SL2W8 PII and just put it at 100 MHz FSB. It'll likely be stable.

The Celeron 300A was hell on wheels and would beat a P2 450 in almost anything. I had a dual Celeron 300A system, @450 of course, that dual booted Windows 98 and NT 4.0. It was a real pain to solder those teeny, tiny wires to enable SMP operation on the slot1 Celerons. Those were the days.

swaaye wrote:

I kinda like the PIII 450. The hot stepping was SL35D which has cache chips of the PIII 600. That means you can often get to 600MHz or more.

Tell me about it! I've got an SL35D in my '99 BX rig at 600mhz. 133mhz bus speed in 1999 baby!

Thanks to everybody for all the responses!

Wouldn't running a P2 300 (SL2W8) @ 450 still have same limitation as just running a P2/P3 450? I mean, the cache running at half-speed. I suppose I'm not seeing the advantage in this scenario. At least with the Celeron 300A @ 450, you get the 128K cache running at the full 100mhz.

Looking at the benchmarks that kixs posted, the Celeron 300A @ 450 does outperform the P2/P3 450. However, it only appears to be a small gain in that it gets about 0.3 to 1 extra FPS in games/benchmarks. Is this enough to justify overclocking a CPU? At most, it seems like a 1-3% gain.

At the time, considering the cost of a P2 450, buying the 300A and overclocking it made tons of sense. But what about today? Is it still a good idea to do something like that when a P3 450 is cheap and easily obtained?

What exactly are the risks in overclocking a 300A? Am I one of the rare cases of a CPU burning up, or was it a more common risk? If it's a riskier alternative to the standard P2/P3 450, then I think I'd prefer to run one of those just for the stake of stability and peace-of-mind.

Of course it makes little sense to mess with overlooking today. Other than to relive it.

At the same clock speed, 512K half speed vs 128K full speed really isn't a tangible difference.

KT7AGuy wrote:

Thanks to everybody for all the responses!

At the time, considering the cost of a P2 450, buying the 300A and overclocking it made tons of sense. But what about today? Is it still a good idea to do something like that when a P3 450 is cheap and easily obtained?

+1
I don't see any practical gain in overclocking vintage hardware. As you just mentioned, the CPU that a mediocre CPU mimicking by overclocking, is also readily available (generally) as cheap as the slow one. Forcing vintage/tired hardware too much is not a good idea IMHO. 😐

tayyare wrote:

I don't see any practical gain in overclocking vintage hardware. As you just mentioned, the CPU that a mediocre CPU mimicking by overclocking, is also readily available (generally) as cheap as the slow one. Forcing vintage/tired hardware too much is not a good idea IMHO. 😐

In my case,since neither of my retro computers get's used very often and even when i use them is for short periods of time,overclocking doesn't pose a big risk and even if something breaks u can replace the part cheaply.

Overclocking these old relics is just to relive it as swaaye pointed out. I used an SL35D in my BX rig as I had a self-imposed target of keeping everything in that particular machine period correct to no later than parts from 1999, i.e. an exercise in building what would have been one of the fastest configurations you could buy in 1999. If you have a such a desire for nostalgia or love tinkering, then use a 300a and have fun cranking it up. Otherwise, just going with the fastest stock speed your motherboard supports would be simpler/ safer.