Upgrading My Mac’s External SSD
I recently replaced a 4 TB 2.5-inch hard drive with a same-sized SSD, with the goal of making it quieter and faster. Instead, it got much slower. As far as I can tell, there’s nothing wrong with the SSD itself (a Samsung T7). The drive tests fine, and I have half a dozen other drives in this family that all work great.
I think the problem is that I put about 3.5 TB of data on it. I was aware that you don’t want SSDs to be super full, but this particular data set grows slowly, so I thought I’d have several hundred GB of free space for the next few years. But I guess that isn’t enough. The drive started out fast at reading and writing, but after filling it up the writes seemed to take forever. Stibium benchmarked them as slow as 1.6 MB/s, but I think they were actually far lower overall.
Samsung doesn’t make a larger T7 or T9, so I ordered an 8 TB SanDisk. That should be plenty of space, and I’ve long used the 2 TB version of that drive. It’s the only non-Samsung SSD that’s worked reliably for me. Unfortunately, I cannot recommend the new SanDisk, at least not for use with a Mac. It kept spontaneously unmounting in the middle of copying files, whether connected to a Thunderbolt dock (via the provided cable) or to a USB hub. Some Amazon reviews note the same problem, even though it overall has 4.6 stars from 81K ratings. In light testing, it did seem to work when directly connected to my MacBook Pro, but I only have three ports and don’t want to dedicate one to this drive.
I replaced it with a Samsung T5, which in theory is slower than the T7, but in actual use it’s much faster than what I had before, and it seems to be reliable.
Previously:
- USB-C Hubs and My Slow Descent Into Madness
- Upgrading an M4 Pro Mac Mini’s Storage for Half the Price
- Using “tmutil associatedisk” With APFS Destinations
- Mac SSD Performance
- USB-C Is Still a Mess
- The Impossible Dream of USB-C
- RocketStor Drive Dock: More Expensive But Reliable
- Highpoint RocketStor 5212 Thunderbolt Dual Drive Dock
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I had the same issue with a T7 which is almost full. In my case adding a windows extended fat partition of 128Mb made it faster, not sure why it worked (read that suggestion in one of Samsung forum if I remember correctly).
It is not always fast with the windows partition, it sometimes take a couple of seconds before it starts getting faster when I access it.
Hope it helps
I use a 8TB ProGrade Digital USB4 SSD as the main storage on my Mac Studio M1 Ultra. It replaced a Sargent 8TB TB3 drive because the latter was QLC flash and even with backups I prefer the higher performance, reliability and endurance of TLC flash. Both worked flawlessly.
Another drive to consider is the Crucial X10 8TB. I’ve had bad experiences with Samsung and have flipped the bozo bit on them. Crucial is a division of Micron and they fab their own flash, like Samsung and unlike SanDisk which sources from Kioxia (f.k.a. Toshiba). I don’t have the 8TB yet, but I do have 2TB and 4TB Crucial X9, they are great drives.
