I got a Samsung T7 external SSD yesterday. It's a USB 3.2 Gen 2 device. Speeds were great. Now, the write speeds are capped at around 431Mbps. Anyone know what's up with this thing? I think I'm going to return it and stick with the T5.
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Slow External SSD Write Speeds in Catalina
- Thread starter jedivulcan
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If you plug your T5 in its write speed is better? Maybe check if there is a firmware update for the T7.
Firmware is up to date. The T5 is roughly the same depending on how it's formatted. Nudges ahead when using ExFAT or HFS+.
847.4 MB/s ExFAT (Uploaded Screencap)
704.4 MB/s APFS (Encrypted)
816.2 MB/s APFS
815.6 MB/s HFS+
755.7 MB/s HFS+ (Encrypted)
Wouldn't go above ~440 MB/s after using it for a few hours. Unplugged it. Came back the next morning. Same thing. Doesn't matter what I format it to.
Does the drive get hot after using it for a few hours? Have you contacted Samsung directly about it?
It got hot after about 20 minutes of sustained use (transferring files to the T7). Haven't contacted Samsung directly.
Maybe the drive is overheating and that could be why it slows down. Could be a defective drive. Did you notice if the T5 got hot after using it a few hours?
The T5 got warm but I never had an instance where it dipped in throughput because of it.
T7 might be defective or overheated. There were instances where it slowed down to a halt but never corrupted anything or panic'd MacOS.
That does not sound normal or good. I would certainly be frustrated with a drive that acted that way. I would just return it for another unit.
I'm sending the T7 back and sticking with the T5.
The T5 is more consistent all around. I did two tests with random files (100gb and 318gb). I know it's sort of extreme to test them like this.
The T7 beat the T5 in the 100gb transfer.
but the T7 tanked in the extended 318gb and the T5 finished first by a huge margin. Yeah. Frustrating.
I would really wonder if this was a bad drive. Does not seem like it should work this way. I would exchange if possible.
Would this still work?
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I don't believe so, but I'm not specifically familiar with its capabilities now.Would this still work?
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I am having same problem. Write speed is very low. It is about 56MBps. Read speed as good as it was when I bought the drive.; Samsung support is not existing at all. They verifying my warranty for more that month and still doing it. My T5 works perfectly. I have forced to buy TB3 external enclosure and add into it 2Tb NVME drive. Now I have 1600MBps write and 2600 read! Still have no idea what to do with T7. Return time is expired already 
Same issue with a Samsung T7 - initially fast writes, but now ~134MB/s (it actually manages ~700MB/s in tiny bursts but falls to 16MB/s most of the time). Read speed is still 900+ MB/s.
Samsung support have issued an RMA and are replacing it (it was just 6 months old). Will see how long the replacement lasts, but I'm not feeling too confident.
Samsung support have issued an RMA and are replacing it (it was just 6 months old). Will see how long the replacement lasts, but I'm not feeling too confident.