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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.
Old ones certainly 'feel' slower, especially when you are accustomed to using a new fast cpu. But I've never seen any benchmarking data that would suggest a trend with age. – Sir Adelaide – 2017-11-17T05:01:43.433
6The apparent decline in processor speed is mostly due to software bloat added with every program and OS update/upgrade. – sawdust – 2017-11-17T05:09:08.453
5Does friction increase on well-worn data paths? :) :) :) – Solar Mike – 2017-11-17T05:32:44.293
@SolarMike, actually YES :D see below. – Vladimir Cravero – 2017-11-17T08:58:15.373
NIce one, learn something every day... – Solar Mike – 2017-11-17T09:02:33.640
@SolarMike well, it isn't friction, but the answer explains it. As an aside, my Pentium 4 runs just as well as it always did. – Baldrickk – 2017-11-17T09:12:05.797
In the old days, disk fragmentation would slow a desktop down. Today, most systems have a scheduled defrag built in. – Walter Mitty – 2017-11-17T11:36:08.633
@WalterMitty also (as far as I know) modern file systems often don't need to do defragmentation as often as old file systems as they are better at planning where to store files. – mathreadler – 2017-11-17T11:55:56.360
@Baldrickk exactly. CPUs are designed so that EM doeas not affect performances, but theoretically it is possible. – Vladimir Cravero – 2017-11-17T13:18:29.667
@mathreadler I haven't kept track of that. It seems unlikely to me since, if the free space is fragmented, the OS has little choice about where to put new files. However, if the defrag happens behind the scenes, the use may be completely unaware of it. Also, disk drives with no moving parts may not be slowed down at all by fragmentation. – Walter Mitty – 2017-11-17T15:19:38.480
@WalterMitty yes if the free space is fragmented, but maybe it is better at avoiding that happening by planning in advance. – mathreadler – 2017-11-17T22:32:15.133