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Comment by tux3 | Hacker News Reader

The room temperature or precise way the paste was applied should not matter. Modern CPUs have very advanced dynamic voltage and frequency scaling (DVFS), which accounts for several sensors, including temperature.

These big x86 CPUs in stock configuration can throttle down to speeds where they can function with entirely passive cooling, so even if the cooler was improperly mounted, they'd only throttle.

All that to say, if GMP is causing the CPU to fry itself, something went very wrong, and it is not user error or the room being too hot.

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This was my first question as well- I thought it had been a long, long time since you could fry a CPU by taking away the heatsink.

As in... what, AMD K6 / early Pentium 4 days was the last time I remember hearing about cpu cooler failing and frying a cpu?

It was some time around then. I remember AMD being late to it vs Intel.

That was SpeedStep? By the time AMD got to it it was just sort of expected and didn't have a fancy name, as far as I know.

Or maybe I'm thinking of something else entirely…

AMD's fancy name was PowerNow! or Cool'n'Quiet.

Athlon era when AMD had no IHS but Intel had one. Intel also had thermal controls that AMD lacked.

I once worked on a piece of equipment that was running awful slow. The CPU was just not budging from its base clock of 700Mhz. As I was removing the stock Intel cooler, I noticed it wasn't seated fully. Once I removed it and looked I saw a perfectly clean CPU with no residue. I looked at the HSF, the original thermal paste was in pristine condition.

I remounted the HSF and it worked great. It ran 100% throttled for seven years before I touched it.

This infamous video: https://www.youtube.com/watch?v=06MYYB9bl70

K6 depended on motherboard having thermal sensors - and which had to properly attach to the CPU in the first place.

Built-in thermal sensing came later.

Yes, this is the point - software should never be able to physically damage the hardware it is on.

If it can, then the hardware is to blame.

As a FW engineer, my software has released the magic smoke a lot.

That's why firmware is often considered a separate category from software even though technically it's the same thing. Software is code that expects the hardware to works as specified, firmware is what achieves that.

If the throttling is not stable it could increase stress on the part by creating a bunch of transient but large thermal cycles through the chip. It would need to have some kind of exponential backoff on throttle so it doesn't immediately try to raise the frequencies when the temperature slightly dips.

I would be interested to see if they had the same result with PTM7950 thermal material instead of paste. I've seen significantly better temps with these modern phase-change compounds, and they essentially eliminate application errors.

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