Transfer Speed very slow

Hi there,

first of all thanks for this great project!

I use a Pi 3B at the moment and i am a little disappointed about the transfer speeds i get.
What can i do to get better results or is this already maxed out?

What do i copy?

  • 2 GB of Videodata (8 Files) from a Sandisk U3 Card using a UNI USB-C Thunderbold 3 Cardreader

Where do i copy it to?

  • I use a Sharkoon Quickstore Pro USB 2.0 Enclosure with a HDD (exFAT)

What are the results?
The results are about 15 Megabytes / s.

What did i try to make it faster?

  • used a Samsung EVO SSD instead of a HDD in the enclosure
  • formatted the HDD to ext4 instead of exFat
  • tried to copy a USB 3.1 Stick instead of a sd card (to see if the sd card reader is slow)

The results were always the same. I didn’t get more than 16 Megabytes per second.

I wonder if i should buy the Pi 4 but i tested it with a Pi 4 of a friend (but only the constellation with my UNI Card Reader with the U3 card coping to the SSD in the enclosure) and the speed was the same! I know the enclosure is only USB 2.0 but USB 2.0 Fullspeed is a lot more than 15MB/s.
On the other hand i read blog articles where people copy 50GB in 15minutes.

So what do you guys suggest?


The Pi 3 generation doesn’t have better than USB 2.0, that’s probably your bottleneck…

1 Like

I know, but why isn’t the Pi 4 faster? Also USB 2.0 Full Speed is theoretically 480MBit (60 MByte) per second.

The Pi 4 has both 2.0 and 3.0 ports, first have to make sure you’re using the right one…

Note that the 3.0 ports are connected to both the internal 2.0 hub and the 3.0 hub; which is used depends on the cable/device connected:

I did not know that, thank you. I ordered a Pi4 and will try it with a Samsung T5. This combination seemed to be the fastest according to vlogs i read.