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There is no fix for Intel’s crashing 13th and 14th Gen CPUs — any damage is permanent
(www.theverge.com)
This is a most excellent place for technology news and articles.
Pentium 2 and 3 had rudimentary protection. They would simply shutdown if they got too hot. Pentium 4 was the first one that would throttle down clock speeds.
Anything before that didn't have any protection as far as I'm aware.