How-To: Boost your Mac's speed and prolong its useful life with easy RAM upgrades - 9to5Mac
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UPDATE: Welches Mac OS Version brauchst du für deinen Mac? - Back Market DE
Teardown des MacBook Pro 13" mit Retina Display von Anfang 2015 - iFixit
Surprise! iFixit says you can't do much to fix or upgrade the 2015 MacBook | Ars Technica