I decided to test the performance of my new Crucial P1 1TB NVMe M.2 SSD. During the first benchmark, the read and write speeds were roughly within expected ranges. However, when I retested, the read speed stayed consistent, but the write speed dropped significantly.
By comparison, my internal drive performed flawlessly with no errors and much higher speeds. Unfortunately, I rely on the external SSD as my primary drive because the internal one only has 256 GB.
I also tried installing Bootcamp on the external drive with a 60GB partition, but it failed.
Additionally, I read that Apple’s SSDs outperform others due to TRIM support. Is enabling TRIM possible for external drives? I’m also considering upgrading to a Thunderbolt 3 SSD for better performance—any thoughts on this?
TRIM isn’t magic—it just helps SSDs manage garbage collection. For externals, macOS treats them as “rotational” by default, so TRIM is ignored. You can force it with diskutil enableTRIM /Volumes/YourDrive, but YMMV. Thunderbolt 3 is 100% worth it if you need speed (40Gbps vs USB 3.2’s 20Gbps), but enclosures cost $$$.
Pro tip: Sabrent Rocket + Acasis TBU405 enclosure = budget beast.
Why not upgrade the internal SSD? OWC sells kits for older MacBooks (ifixit has guides). If it’s a newer T2 Mac, ignore this.
For externals, Thunderbolt is your friend, but if $$ is tight, split your workflow: keep macOS on the internal 256GB and run Windows/mass storage off the external.
Or if you feel the speed is too slow, you can try to clean more space for it, the tool iBoysoft DiskGeeker for Mac can help you a lot.