Well - I never tried this on an AMD core yet but I can confirm that Intel cores are "hard" (in physical terms at least).
We had a dead CPU (physically fine) and some guy sent in a crushed CPU (looked like a tank had driven over it). He said all he did was "try to put the FHS on".
To try and "recreate" his conditions, I took the CPU, a good screwdriver and started whacking it. Only after the 6th whack (Sharp end, full strength) did the core finally chip & explorde.
So, that is quite good quality there - I can confirm that. Haven't been bothered to do that to an AMD CPU yet, though I am getting tempted

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