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Tested: Windows 11 Pro's On-By-Default Encryption Slows SSDs Up to 45%
(www.tomshardware.com)
This is a most excellent place for technology news and articles.
Even before Apple added custom chips, just using the intel AES instructions, their encryption performance penalty was like 3% https://archive.techarp.com/showarticle0037.html?artno=877&pgno=1
Microsoft is doing something very wrong to end up with this much overhead