Question What's the slowest CPU you have tortured in your history of personal computing?

[igor_kavinski]

I was thinking of Det0x when this question popped up in my head. I was kinda realizing that Det0x gets to experience performance of a low end CPU at least 10 years before they are released to the general public, by tuning his current high end CPU to the extreme. Maybe even 15 years ahead of time? Maybe Det0x can provide more data on that with previous benchmarks (but not sure if he has ever had a low end CPU to play with).

So my question is, what's the slowest CPU you have tweaked/overclocked to get the best performance out of and how satisfied were you with it? Mine was Celeron 700 OCed to about 1 GHz. It was enough to let me enjoy Doom 3 without having to buy a new CPU so that was great but it sure ran hot running that game!

 

[Tuna-Fish]

The legendary Celeron 300A.

The top-end Intel CPUs of the time were Pentium II 450MHz, with 100MHz FSB and 512kB external ½-rate L2 cache. Alongside the top-end model, Intel introduced a "low-end" model on a separate die that had 128kB of full-rate L2 cache included on die, fixed clock multiplier of 4.5, and FSB of 66MHz. These CPUs were made on the same process and had the same core architecture as the proper P2:s, they were just artificially clocked lower for market segmentation. Almost immediately after release, people realized that if you just took a 300A and plugged it into a 100MHz FSB board, it would run at 450MHz.

And it was in many loads actually faster than the much more expensive top-end model. The difference being that the included 128kB cache wasn't just double the throughput, but also significantly lower latency, as it was on-die.

I think I ran that thing until I got an Athlon Thunderbird two years later.

 

[Insert_Nickname]

So my question is, what's the slowest CPU you have tweaked/overclocked to get the best performance out of and how satisfied were you with it? Mine was Celeron 700 OCed to about 1 GHz. It was enough to let me enjoy Doom 3 without having to buy a new CPU so that was great but it sure ran hot running that game!

I think there are 2 parts to that question. The "slowest" CPU I've tweaked to great performance would be the Celeron 300A. Those things are legendary for a reason.

The slowest CPU I've ever used was an ordinary Pentium 3 1GHz (I think). That thing was so slow and bogged down at the time (late '00s), that it took literally 30 minutes to just get Windows XP running. Oddly enough it suffered a major malfunction a little later. I can't imagine why.

The legendary Celeron 300A.

The top-end Intel CPUs of the time were Pentium II 450MHz, with 100MHz FSB and 512kB external ½-rate L2 cache. Alongside the top-end model, Intel introduced a "low-end" model on a separate die that had 128kB of full-rate L2 cache included on die, fixed clock multiplier of 4.5, and FSB of 66MHz. These CPUs were made on the same process and had the same core architecture as the proper P2:s, they were just artificially clocked lower for market segmentation. Almost immediately after release, people realized that if you just took a 300A and plugged it into a 100MHz FSB board, it would run at 450MHz.

And it was in many loads actually faster than the much more expensive top-end model. The difference being that the included 128kB cache wasn't just double the throughput, but also significantly lower latency, as it was on-die.

I think I ran that thing until I got an Athlon Thunderbird two years later.

Honourable mention to the humble Morgan-core Durons. Those things where absolute budget beasts. Only had 64KB L2, but had the full Athlon 128KB L1, so you had 192KB total. Which was respectable at the time. Further, it was on-die and full speed.

One of those and an ECS K7S5A, and you had a killer combo. You could even reuse your old SD-RAM in it, until you could upgrade to DDR.

 

[Pohemi]

Celeron 700 as well, but as it was one of the first PCs I owned, I didn't OC it much, and I think to only 800MHz at most.

First chip I really hammered on with OCing was the mobile Athlon-XP 2500+ (Barton core) in an Asus A7N8X-e deluxe. OC'ed from 1.8GHz to 2.5GHz. This was the largest boost I ever got from OC'ing. I still miss those chips, they were a lot of fun to tweak.

 

[Markfw]

The original 80286. I overclocked it to 7 mhz.

 

[igor_kavinski]

The original 80286. I overclocked it to 7 mhz.

I wonder which software you wanted to run fast with that speed and if you still use that software?

I know I used to keep my 486DX2-66 on Turbo mode (66 MHz) instead of 33 MHz non-turbo so it would play Doom/Doom2 well. I think the non-turbo mode was for compatibility with really old software that would get erratic at higher speeds.

 

[igor_kavinski]

The slowest CPU I've ever used was an ordinary Pentium 3 1GHz (I think).

There must have been something wrong with that chip or mobo from the beginning (maybe throttling due to bad TIM?). I know that my Celeron@1 GHz served me fine well into the days of WinXP SP1 at least. I even sold it to a friend which I don't remember but he reminded me about it just a year ago. I tried to search my memory but I guess my brain didn't deem it necessary to keep it tucked away somewhere in the recesses of my organic RAM. I have a vague recollection of meeting my friend to sell him something but what exactly, my brain has no clue.

 

[Markfw]

I wonder which software you wanted to run fast with that speed and if you still use that software?

I know I used to keep my 486DX2-66 on Turbo mode (66 MHz) instead of 33 MHz non-turbo so it would play Doom/Doom2 well. I think the non-turbo mode was for compatibility with really old software that would get erratic at higher speeds.

compiling MS basic, then Turbo Pascal. Have not used either in 30 years.

 

[ondma]

Probably the "worst" in relation to how it should have performed in the context of the times was a Celeron (something like 800 mhz) running in a desktop with Win 2000. The actual "slowest" was a Pentium 200 mhz in the first computer I ever had. Cost like 2k dollars. However that was in the infancy of cpus, so it is understandable.

 

[scannall]

1 Mhz 6502, overclocked to 2 Mhz using a faster clock crystal. Worked great, except a lot of games depended on that 1 Mhz so they ran too fast. Built a little daughterboard with a 1 Mhz and a 2 Mhz crystal, and a switch to flip between them.

 

[Markfw]

1 Mhz 6502, overclocked to 2 Mhz using a faster clock crystal. Worked great, except a lot of games depended on that 1 Mhz so they ran too fast. Built a little daughterboard with a 1 Mhz and a 2 Mhz crystal, and a switch to flip between them.

I had that problem on my "Leading Edge" (that was the brand name) 4.77 mhz. I put a Vic 20 ship in it, and it ran like 7 mhz.

 

[clemsyn]

A Cyrix 5x86 with FSB at 66 to get 133mhz (I think it was 100mzh or 120mhz with) Played Quake on it.

 

[Insert_Nickname]

There must have been something wrong with that chip or mobo from the beginning (maybe throttling due to bad TIM?). I know that my Celeron@1 GHz served me fine well into the days of WinXP SP1 at least. I even sold it to a friend which I don't remember but he reminded me about it just a year ago. I tried to search my memory but I guess my brain didn't deem it necessary to keep it tucked away somewhere in the recesses of my organic RAM. I have a vague recollection of meeting my friend to sell him something but what exactly, my brain has no clue.

I have no idea what was wrong. Was an old OEM box - HP from what I remember. It shouldn't have been that slow.

Hence, it got chugged. I didn't see much point in keeping it.

 

[Doug S]

Technically not overclocking, but the first computer I paid for myself was a Mac Plus upgraded from the default 8 MHz to a blazing 16 MHz. It involved replacing the CPU with a higher rated part.

Can't remember if I did the upgrade myself or bought it already upgraded.

 

[igor_kavinski]

Can't remember if I did the upgrade myself or bought it already upgraded.

Takes a very busy mind to forget something like that

 

[Ajay]

My first overclocking experience was with a PII 266, it would only hit 300Mhz (boohoo). Celeron 300A was awesome @ 450 Mhz. Then a PIII 550 @ 733Mhz - not bad. Then AMD K7s for a while.

Earliest computer I owned was a C64 - but I didn't mess around with any till I built my own.

 

[moinmoin]

I know it's not a PC exactly nor involves any OC'ing but the title for some reason made me think of the lowly slow Zilog Z80 and this piece of history:

 

[MangoX]

I took a Duron 750 to 900mhz that was sick. Ran hot, remember briefly cooling it with a Thermaltake orb. Also a i7 920 2.66 stock to 3.33ghz. And as well my Sandy Bridge 2500k to 4.6ghz

 

[biostud]

Does a "turbo" button count as overclocking?
We had a 386sx that could switch between 16 and 25mhz.

But otherwise a Pentium II 266 was the first I overclocked.

 

[aigomorla]

The legendary Celeron 300A.

THESE WERE NOT SLOW FOR ITS TIME.
They were wickedly FAST when you flipped that jumper on your Abit motherboard to go from 66mhz to 100mhz.
Then they gobbled Pentium II 400's for breakfast lunch and dinner while costing half the price.
It would be like how Dodge said you guys want a sick charger... here's the Demon Scat pack BAM!

Of course intel was NOT happy with it.
Thats where they started locking CPU's on the CPU side.
When a 150 dollar processor started ballarina dancing with a 650 dollar processor if my memory serves me correctly, that was one sick processor that still belongs in the league of overclocking legends along with Conroe/Kentsfield Wolfdale/Yorkfield and Nehalem/Gulftown class processors.

If you want to talk about slow torcher.... lets talk Smithfield/Prescott.

Intel® Core™ Processors, FPGAs, GPUs, Networking, Software

Browse Intel product information for Intel® Core™ processors, Intel® Xeon® processors, Intel® Arc™ graphics and more.

www.intel.com

Want them high overclocking numbers.... yup got it... over 6ghz+ overclock easy baby~!
Look at its base clock...


What them high thread counts... yup got that too, hyper threading started on these guys which was called Netburst back then, and was dumped because the cores were too slow for any benifit until we saw them in Nehalem.

NetBurst - Wikipedia

en.wikipedia.org

Why am I bashing on that CPU?
Because AMD @ half the clock numbers were doing circles around them with the Opteron 160 (Manchester), calling intel "noob", until Conroe aka Core2Duo said oh no you didn't.

It was so bad, an Opty 160 or 165 170 @ 2.2ghz would man handle a prescott at 7ghz in everything you threw at it, including SuperPi.
The CPU made intel completely side rail the roadmap and jump on laptop processors where they found a golden egg in what was known as "Yonah", which evolved to the legendary Conroe later on.

Yonah (microprocessor) - Wikipedia

en.wikipedia.org

So my vote goes to the ever so pathetic Pentium D - aka Smithfield / Prescott Which i have had, and it was a very good foot warmer.

Oh did i forget to mention, they were also known as expensive as hell space heaters for all the heat they threw out for how little performance you got from them?
You think im kidding? google Pentium D space heater.

 

[Hans Gruber]

Intel Q6600 quad core stock 2.4ghz to running 3.8ghz and 3.6ghz for the life of the CPU. I used a Thermalright Ultra 120mm for air cooling. I had 8GB of dual channel memory on 2GBx4 sticks running DDR2 1000mhz. It seemed like when standard computers still had 4GB of ram while I had 8GB of ram for 4 or 5 years. Paired with my 8800GT GPU, my computer was a powerhouse for years. I had a RAID 0 with Samsung 500GB drives.

 

[igor_kavinski]

Intel Q6600 quad core stock 2.4ghz to running 3.8ghz and 3.6ghz for the life of the CPU.

Mine was a Q9300 not overclocked (I think) with 8GB RAM and Geforce 9600GT. I played Crysis on that and I think it was a fun experience (I probably dialed down the settings even though I don't remember doing that but it was the most visually stunning game I had played thus far). Only the last level seemed to be too much for my PC to handle coz I remember being a bit frustrated about the slowness.

 

[Shmee]

Probably either the Core 2 Duo E6320 or the Pentium dual core E5200. The E5200 was a Wolfdale and had higher base frequency, but lower FSB, meaning its core multiplier was quite a bit higher. This made it a pretty good CPU to OC, plus being on 45nm process vs 65nm for the E6320 helped. But the E6320 had double the cache at 4MB.

 

[igor_kavinski]

My 440BX mobo's BIOS probably didn't have any OC options that I can remember (it was just some cheap model my dad got for me. I don't even remember the brand. Maybe PC Partner?). I somehow got my hands on SoftFSB (again, my memory fails me) and I didn't know what I was doing.

I just knew that if I selected 440BX in it and raised the FSB from 66 to 100 MHz, I would hear this increased hum (it wasn't the fan) that indicated something just went into overdrive and the Celeron started working at 1 GHz. It was very convenient to be able to OC from within Windows on demand. It was my own primitive turbo boost before Intel introduced their automatic version and millions of enthusiast overclockers were suddenly silenced

 

[Hans Gruber]

Probably either the Core 2 Duo E6320 or the Pentium dual core E5200. The E5200 was a Wolfdale and had higher base frequency, but lower FSB, meaning its core multiplier was quite a bit higher. This made it a pretty good CPU to OC, plus being on 45nm process vs 65nm for the E6320 helped. But the E6320 had double the cache at 4MB.

Almost forgot. I built my dad a Intel E6300 Core2 Duo 1.83hz stock in 2006/07. He used that computer for 10 years until I forced him to retire it. From day 1 it ran flawlessly OC'd from 1.8ghz to 3.2ghz. That was when I realized AMD was doomed. And they were for more than 10 years. That computer had a Thermalright Ultra 120mm cooler on it. I think I bumped the voltage on it once or twice in 10 years. Silicon degradation only needs a quarter of a volt bump. If it was 1.35v it went up to 1.375v.

I bought him an adapter and he still uses it on a Kaby Lake Pentium Dual Core 4620. Now that PC needs to be retired. He still thinks it's good. So I gave my mom one of my Zen 2 3600's with water cooling and my GTX970 with new fans. He wants something better now.