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Original poster
Apr 19, 2002
New Zealand
Thought I'd start a thread as I haven't been able to answer my question using search.
I have a 4,1 Mac Pro flashed to 5,1. It has a 250 GB Samsung 840 SSD and 3 TB Seagate HDD which have been turned into a 3.25GB DIY Fusion drive.
At this stage with a full Mavericks install, is it A) necessary to activate TRIM and B) safe to turn it on with a DIY Fusion drive?


macrumors 65816
Oct 11, 2013
Baltimore, MD
Not necessary at all, and definitely safe. Currently running the 1.12TB version with an 840 EVO and a Hitachi 1TB with TRIM enabled. Don't notice much of a difference with TRIM vs without TRIM, but just in case. That terminal command will do it for sure, just takes a reboot.
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