Turbo button not pressed, run at lower speed than rated
Turbo button pressed, run at rated speed
No rebate, sell at a huge margin
Rebate, sell at a minimum margin
It was more a situation of being a computer nerd at exactly the right time and place so that it was possible to really impress adults with minimal actual effort
Same reason I had a spare 286 lying around
I was always trying to find ways to improve the performance of my systems when I was a kid. Tweaking configs, removing bloat, stealing components from my parents systems. I would've loved to have tried what you did!
Oh, I know that feeling.
Blew one teacher's mind by doing animations on the RISC OS machines at school, they didn't know it was even possible.
4D-maze visualisation and route-finding at university.
What was weird was all the times I've shown people Word Lens or Google Translate, augmented reality translations blew the minds of other developers even a decade after that was demonstrated.
Right time and place.
More importantly, a hot CPU wouldn't perform worse, it would just break at some point when a computation got the wrong result.
By swapping crystal oscillators with a higher frequency.
Really put me in my place with this one. Nice work.
>I didn’t even measure the clock speed - just wrote a little program (I think it was in QBasic) that calculated factorials or something (don’t remember the details), then measured performance difference between no cooling, ice water, and liquid nitrogen.
>My measurement technique was extremely simplistic - how much wall clock time does it take to do this computationally-intensive task. It ran faster with ice water, and even faster with the liquid nitrogen (until it died from condensation).
There is no world in which a 286 has a program that runs "slow" without cooling, and fast with cooling. If a clock speed "needs cooling", it's because the CPU crashes otherwise. If jdenning changed the crystal, THAT'S what increased the CPU speed. They seem adamant that wasn't the case though.
I truly don’t understand why this anecdote seems to be offensive - but let me assure you, I’m claiming no scientific discovery or prodigious understanding of cpus here.
It was neat - computers, liquid nitrogen, color charts.. in the early 90s. That kind of shit got you scholarships back in the day.
AFAICT doing interesting but ultimately trivially complicated stuff as a youngster can still result in scholarships etc, Ahmed Mohamed comes to mind.
I’m truly sorry if my childhood anecdote has inadvertently spread misinformation on this topic :)
somebody else mentioned the possibility that the cooling did something to the crystal oscillator, but I think there are another two explanations that either alone or in combination might explain what happened: unreliable narrator (OP was very young when the memory was formed) and external influence - his dad or teacher might have done the overclocking which might have been beyond his understanding and therefore notice at the time.
either way there's no reason to take anecdotes uncritically.
It is in Bayesian reasoning.
> either way there's no reason to take anecdotes uncritically.
> Because in this thread there are only theoretical explanations why it cannot be
No, the explanations are referring to the mountain of evidence based on the physics of the chips and the known characteristics of the chips of the time. That's not theoretical, that past observations.
At any rate, sounds like a really fun high school project!
The 286 came out in 1982 but it wasn't until ~2000 (with the release of the Pentium 4) that thermal throttling was introduced.
From ~1995-2000 if the CPU got over temperature, your PC just turned off immediately. And prior to ~1995 if you ran a CPU without a heatsink it could overheat and destroy itself. We just had to be careful not to do that :)
I will leave it to history to judge if I truly earned that blue ribbon
You are stating that providing better cooling to a 286 improved it's performance in the terms of calculating faster.
This is, flatly, false. If you have a 286 clocked at 8mhz, it doesn't matter how much you cool it, it will still run at 8mhz, and still only execute the same number of instructions per clock.
To make a 286 perform more calculations per second, you MUST increase it's clock rate, directly, by installing a faster oscillator. Running at a high clock rate reduces the time each gate in the circuit has to settle to a state, high or low. This can cause the CPU to have what it experiences as "random" gate flips, that will eventually crash it. To fix this, you can increase the voltage, which can force the gates to stabilize faster. This creates more heat. This heat is what more cooling can extract.
In modern CPUs, the voltage, clock speed, and cooling can all be varied independently (within limits) to acheive whatever is desired: quietest/coolest performance, fastest clock, highest performance, etc.
This is not true on a 286.
If the CPU does not crash with a faster oscillator, extra cooling will not increase it's performance.
I can see why you won! In the early 80s, just building the clock circuitry to generate arbitrary frequencies for the CPU only would have been quite an engineering feat.