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I want to know definitively if I can build computers using USED processors and expect the same performance as new processors of exactly the same make and type with exactly the same motherboard and drives.
I have searched for several days now online without finding a definitive answer or any studies that explain whether CPUs decline in speed after extended periods of use. I want to know if a used but functional CPU will provide the same performance as a new-from-the-box CPU.
Edit: To be clear, I am looking for a definitive scientific answer, supported by evidence, so that I can make informed decisions when building computers and refurbishing computers. I think this different enough from other questions asked that relate to this topic.
CPU processing speeds will decline as the temperature increases and heat transfer compound may need to be replaced, but aside from this will a CPU lose overall processing power or 'wear out' after extended use?
If so, what causes this? I have heard of electron migration in motherboards, but could this actually cause a CPU to slow down with use? From what I understand about electron migration, it is more likely to cause outright failure of the CPU rather than a gradual slowing of processing speed.