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Comment by krylon | Hacker News Reader

Something similar might have happened with Celeron 300 CPUs, I recall they could be overclocked to 450MHz as well without trouble. I think they didn't have as much cache as the Pentium II, but the increased clock rate meant you could get a pretty fast CPU for cheap.

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Not only could you overclock the Celeron 300A, with the right motherboard you could run two of them in a dual CPU configuration.[0] This was my first high performance computer! Initially I dual booted Windows NT 4 and Windows 98, but soon enough Windows 2000 was released and allowed me to make practical everyday use of the two cores. It was an extremely satisfying computer to own.

[0] https://en.wikipedia.org/wiki/ABIT_BP6

The ABIT BP6 was a legend; and it was kind of amazing that Intel hadn't done their "licensing" or whatever such that it was impossible to make; good thing clones were around.

Of course now every CPU is its own multiprocessor machine, but back then it was a real screamer, and unless you could get multi-CPU Windows it was a real reason to poke around with Linux.

I had one of those with dual Celeron 366's running at 533

It worked great from about 1999-2002 when I upgraded to an Athlon 1700, then an Athlon 64. I finally had 2 CPU cores again with the Athlon 64 X2 around 2005.

How does the memory work on that board? Is there a single northbridge with a single memory controller that both CPUs can somehow utilize?

The 440BX chipset supports two CPUs, so it is organised so that the northbridge is shared between the CPUs[1]. I found a datasheet[2] and from a skim and it looks like the front side bus is also shared between the CPUs.

[1] This is from the era before the memory controller / northbridge was integrated with the CPU.

[2] https://datasheet.octopart.com/FW82443BX-Intel-datasheet-533... - page 12 has the basic system diagram

It was similar to other dual-processor boards out at the time; those were just very expensive and for very expensive "server" CPUs.

I remember having an older Pentium Pro motherboard with dual sockets.

I remember drooling over the price list of a local computer store back in the day. A dual-socket board for a Pentium Pro cost DM 2,000, and a Pentium Pro 200MHZ cost about as much, so just the board and two CPUs were DM 6,000 (roughly € 3,000, not adjusted for inflation).

A friend had that setup... was definitely fast for the price at the time... I ran an OC'd duron to 1.1ghz about a year later iirc (2000 era)... also ran Win2000, switched from OS/2 Warp and never really looked back. Win2k was very nice, and mostly stuck with it until Win7, the couple times I tried XP sucked, though MCE2005 was very ice, shame MS and cablecard pretty much killed it.

IIRC the Celeron chips coming out of the fabs tested better than Intel expected with far more of the batches being rated as stable as higher-spec units. This lead to a shortage of cheaper units that people were trying to buy and an excess of faster units that people didn't want to pay for. To avoid both missing sales and having a lot of stock sat in warehouses, many batches of Celeron chips that had tested fine to be sold as the faster models were binned with those that were only rated for the slower speeds. This meant that if you were lucky you could safely overclock the cheaper units by officially extravagant amounts, without extra special cooling arrangements or other hacks, and many did.

You could tell (at least initially, I'm not sure if Intel changed this later) from part of the product code that you definitely had one of the units from a batch that tested fine at the higher speeds, so it wasn't that much of a gamble either.

We referred to them as Silly-ron CPUs.

Yep, the Celeron 300A: https://www.anandtech.com/show/174/3

The Celeron 300A might still be the best bargain in CPU history. I put together a bunch of PCs with them for myself & friends/family. Not all of them could get to 450mhz, but all of them were able to clocked much higher than 300. And with the L2 cache on the chip, it already was better clock-for-clock than contemporary products.

While from an objective amount 50-150mhz is peanuts in today's terms, that was a huge step up relative to the original speed.

I did the same with a Celeron 300A at 450. The other great thing about that era was the 440BX chipset supported so many CPUs. I upgraded the same Slot 1 board from that 300A@450 to a Celeron 900 in a "slotket" socket to slot 1 adapter and used it for another 3 years.

5820K and 5960X have hit nearly similar overclocks in recent memory - chips with 3.4 and 3.3 GHz all-core turbo had a majority of chips (~75-79%) going to 4.5 GHz. 4.5/3.3 = 36% overclock, which is quite high by modern standards.

Sandy Bridge and Sandy Bridge-E were fantastic overclockers too with many samples going to 4.7 GHz (even on HEDT!).

Broadwell-E, too, could hit some solid clocks if you were willing to push more voltage... a lot of people got later samples to 4.7 GHz despite the numbers being closer to 4.3 in SiliconLottery's tests. Probably an uncomfortable amount of voltage and heat, but, Broadwell itself wasn't as bad as people took it to be, just the prices, and the L4 cache on Broadwell-C limiting the core clocks.

https://en.wikipedia.org/wiki/List_of_Intel_Core_i7_processo...

https://siliconlottery.com/pages/statistics

This is somewhat of a function of Intel not really pushing clocks in those days. 3.3 GHz all-core turbo is nowhere near what the silicon could deliver - generally I would punch in 4.1 GHz all-core on my 5820K and that would be stable without any other (explicit) settings adjustments.

And that is a factor of the TDPs - in those days TDP on desktop was expected to cover your max boost under a (reasonably) worst-case load. It has been a thing for a long time in laptops, but the desktop market was different. AMD was actually the one who introduced the "boost TDP is higher than box TDP" concept (aka PPT) to the desktop market with Ryzen 1000 - and then Intel started following suit once they started ramping up core counts and clocks with the 8700K/9900K.

But 140W is actually plenty for a hexacore or even octocore running at 3.3 GHz and even under a worst-case load scenario... and 91W is plenty for a quad-core running at max turbo too. The numbers weren't as phony back then.

https://www.anandtech.com/show/10968/the-intel-core-i7-7700k...

https://www.anandtech.com/show/8426/the-intel-haswell-e-cpu-...

Especially those manufactured in Malaysia, as they could be overclocked more successfully than the 300As made in Costa Rica. Fun times.

I seem to remember that the 300A overclock was first published by Tom's Hardware - a site started by a German medical doctor, as implausible as that sounds.

I was trying to confirm this, but he didn't claim credit for that in this interview: https://www.tomshardware.com/reviews/20-year-anniversary,455...

P.S.

Also, some twenty years ago another MD rewrote the Linux scheduler, because he wanted better interactive performance: https://en.wikipedia.org/wiki/Con_Kolivas

The first to do it was probably the first to touch the CPU given how established over clocking was by that era. So it could be tom but it's just not that significant if it was or wasn't.

Yeah, "let's see if I can overclock this a bit" was the first thing many people did as soon as they got any new chip. The 300A was notable both because of how far they could be pushed but also how it worked for basically all of them & not outliers.

a myth, Malaysia/Costa Rica was packaging plant designation and had nothing to do with binning or actual fabs.

No. It was a proper Pentium II chip, originally binned as a 450Mhz chip. There was a shortage of the low end chip and they re-badged a bunch of high end chips to fill a whole in the market.

Tells you a lot of CPU production economics.

I did that. My first gaming computer was a Celeron 300 overclocked to 400 with a 3dfx card. At the time celerons we're just getting off the ground and there was virtually no difference in performance - just a much cheaper price!

I believe the smaller cache was the reason it could overclock so high; a similar story happened later in the Netburst era, when the ~2.4GHz Celerons could go over 4GHz with sufficient cooling and sometimes a slight increase in voltage.

This wasn't really overclocking. Intel ran out of PII-300's and sold a bunch of of PII-450s as PII-300s to fill the whole in the market.

CPU economics are weird.

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