We know SSD is so much faster than traditional HDD and there's no doubt about that, but in actual use it depends on cases. I was copying 100GB of files from a uSD to a Samsung T5 drive, and I can barely get 9MB/s, but the same thing with a 7200RPM HDD via USB adapter and a hub I can easily get 20MB/s. It was not the HDD caching as it sustains the speed and keep rising, was it the USB cable I used !?

I've read that some cables, especially those with one end USB-A and the other, USB-C have issues in that not only do cables vary but the C end orientation has profound effects. If you use any cables of this sort try flipping the C end over.

The total speed of the transfer will depend upon teh drives, the drivers, the connections/controller, and how well the buffer space can stage in memory (with depends upon total free RAM and the CPU). USB4 is FAST, but USB3 has multiple speed levels depending upon other factors. (All USB3 is NOT the same!) USB2 is much slower, and USB1 should never be encountered. Proper SATA with a single device per channel is very fast, but ANY controller slows down if it has multiple devices fighting for bandwidth.

(The fastest enterprise F-W SCSI controllers I have ever used maxed out with 5 active drives. They could handle 15 easily, but any more than 5 SSDs and the total speed dropped.They could handle 12 rotating rust drives with no slowdown, but less maximum speed.)

The speed of your transfer will be the speed of the TIGHTEST bottleneck in the data flow path.

Physically speaking, a solid-state drive has none of the "mechanical latencies" that are associated with disks. The first, "seek time," is the time required to move the read/write mechanism to the proper track. The second, "rotational latency," is the time required for the desired piece of data to spin underneath it. Although these delays are measured in "mere milliseconds," they are significant.

I still have a box of unrecoverable "spinning platter" drives which contain data that I have now forever lost. It is for this reason alone that I no longer use that kind of drive. (And, why I now make multiple copies of my SSD's. Just in case.)

Lesson learned then . Which reminds me. It is coming up on the time to do the 'yearly' backup and store off site.

On topic, it is hard to say where the problem lies for writing. Caches, cable, machine, port being used (like a 2.0 USB port), etc. Most times read time is the most important item when it comes to storage devices. Unless it is a backup in which case read/write time isn't so important.

Yeah, I found some such cables can't do quick charge until flipped !

As far as my experience goes, mechanical drives are more 'reliable' than SSD in a way, due to the use of magnetic media instead of electronics components. I too got many bad spinning drives, most of them are noisy clicking due to the head can't 'home', or some other mechanical problem. On most of the bad spinning drives I still managed to partially recover the data after retry reading, but on the SSD or flash drive, depends on which part it failed it may total lost. I've got both an early Sandisk flash and a SSD that randomly 'disappear', so that I would not go with too high capacity on one drive, and make multiple backup as well.

It's important to distinguish between "memory sticks" and true "SSD drives." Memory sticks are based on "flash" technology, which causes them to be very slow to write information. However, their true purpose is to preserve information for future reading, with no power consumption and minimal cost.

The good news is: "'true' SSD technology is now 'dirt cheap.'" (And: "youuuge!")

(If you actually need "removability," the memory-cards used in digital cameras are also available, with appropriate USB interface devices. But the memory units are very small – heh, "no surprise there" – and thus very easily lost.)

FYI both memory sticks and SSD drives use flash memory. I am not sure what is true SSD technology... The cheap memory sticks might use older EEPROM technology but I would assume that USB 3 memory sticks use NAND as well. For T5 max transfer speeds you need to be plugged into a USB 3 port and have UASP mode enabled.

A quick search found a number of threads reporting T5 slow speeds and one thread where replacing the cable helped for awhile. One thread only showed 22MB/s when connected to a USB 2 bus.

There is no DEVICE that is the solution for that. BACKUPS are the solution for that. Multiple copies is one form of backup.

In my experience, when an HDD is dying, there will be signs. If you act soon enough, you should be able to recover most of, if not all of the data.

SSDs might be overall more reliable than HDDs, but when they're ready to die, they'll go without saying goodbye.


If your USB devices are bus-powered, use separate USB ports or a powered hub. Some devices will still work, but slower if they don't get enough power.

Yeah that's what I said, depends on the type of flash in use and the bus design to result in different speed...

Right, I should have used separate power on the hub to get better speed.

Very true, especial early types of SSDs are not reliable enough to replace HDD. I got an early 60G one that suddenly 'disappeared' without saying goodbye !