Given the motherboard and RAM will also generate quite some heat, if the case fan profile was conservative (he does mention he likes low noise), could be the insides got quite toasty.
Back when I got my 2080 Ti, I had this issue when gaming. The internal temps would get so hot due to the blanket effect of the padding I couldn't touch the components after a gaming session. Had to significantly tweak my fan profiles. His CPU at peak would generate about the same amount of heat as my 2080 Ti + CPU I had then, and I had the non-Compact case with two case fans.
[1]: https://michael.stapelberg.ch/posts/2025-05-15-my-2025-high-...
I also have a fractal define case with anti noise padding material and dust filters, but my temperatures are great and the computer is almost inaudible even when compiling code for hours with -j $(nproc). And my fans and cooler are much cheaper than his.
That should of course be sound padding...
Intel specifies a max operating temperature of 105°C for the 285K [1]. Also modern CPUs aren't supposed to die when run with inadequate cooling, but instead clock down to stay within their thermal envelope.
[1]: https://www.intel.com/content/www/us/en/products/sku/241060/...
Because CPUs can get much hotter in specific spots at specific pins no? Just because you're reading 100, doesn't mean there aren't spots that are way hotter.
My understanding is that modern Intel CPUs have a temp sensor per core + one at package level, but which one is being reported?
Anyway, OP's cooler should be able to cool down 250W CPUs below 100C. He must have done something wrong for this to not happen. That's my point -- the motherboard likely overclocked the CPU and he failed to properly cool it down or set a power limit (PL1/PL2). He could have easily avoided all this trouble.
And yeah, having Arrow Lake running at its defaults is just a waste of energy. Even halving your TDP just loses you roughly 15% performance in highly MT scenarios...
I did not overclock this CPU. I pay attention to what I change in the BIOS/UEFI firmware, and I never select any overclocking options.
Also, I have applied thermal paste properly: Noctua-supplied paste, following Noctua’s instructions for this CPU socket.
https://www.techpowerup.com/review/intel-core-ultra-9-285k/2... lists maximum temperature as 88.2C with the previous gen NH-D15 cooler.
I have followed his blog for years and hold him in high respect so I am surprised he has done that and expected stability at 100C regardless of what Intel claim is okay.
Not to mention that you rapidly hit diminishing returns pass 200W with current gen Intel CPUs, although he mentions caring able idle power usage. Why go from 150W to 300W for a 20% performance increase?