and passed it over to them for them to copy.
The file was around 1.2gb, and they said it was going to take 22 minutes to copy to their machine. I thought this seemed a long time, even though it was a 'class 1' Micro SD.
This got me thinking about the whole speed of SD cards, adapters, USB sticks, etc. etc.
As I had quite a bit of time on my hands (fat chance), I decided to do a bit
of testing. My laptop has a USB 3 port, as well as a couple of USB 2 ports and a
built-in SD card reader. I also had:-
1 Transcend USB 3 card reader
1 USB 2 card reader
1 Kingston Micro SD Card Reader
1 Generic Micro SD Card reader
1 USB 3 64gb Memory Stick
1 USB 2 4gb Memory Stick
1 Sandisk Ultra 32gb Class 10 Micro SD card
1 Sandisk 2gb Class 1 Micro SD Card
1 Samsung 32gb Class 10 SD Card
To do my testing, I used the excellent HD Tune, and because I had data on most of the cards, I only did read test. The table below summarises the results.
|Card Type||Card Size||Manufacturer||Class||Interface||Read Speed MB/s||Access Time ms|
|Micro SD||32gb||Sandisk||10||Transcend USB 3 Reader||41.7||0.845|
|SD Card||32gb||Samsung||10||Transcend USB 3 Reader||41.4||0.587|
|SD Card||32gb||Samsung||10||USB 2 Reader||23.2||0.582|
|Micro SD||2gb||Sandisk||1||Transcend USB 3 Reader||21.8||0.797|
|SD Card||32gb||7DayShop||10||Transcend USB 3 Reader||21.7||0.904|
|Micro SD||2gb||Sandisk||1||Built-in Reader||19.1||0.585|
|SD Card||32gb||7DayShop||10||USB 2 Reader||18.5||1.14|
|Micro SD||32gb||Sandisk||10||Kingston USB 2Adapter||17.6||1.04|
|SD Card||32gb||7DayShop||10||Built-in Reader||17.1||0.729|
|Micro SD||2gb||Sandisk||1||Kingston USB 2 Adapter||17.1||0.838|
|SD Card||32gb||Samsung||10||Built-in Reader||15.8||0.409|
|Micro SD||2gb||Sandisk||1||Generic USB 2 Adapter||0.9||1.55|
|USB3 Stick||64gb||7DayShop||?||USB 3 Stick||71.7||1.08|
|USB3 Stick||64gb||7DayShop||?||USB 3 Stick in USB 2 Slot||29.2||1.3|
|USB2 Stick||4gb||Generic||?||USB2 Stick in USB 2 Slot||26.7||0.755|
|USB2 Stick||4gb||Generic||?||USB2 Stick in USB 3 Slot||28.7||0.571|
As with most things in this life, you get what you pay for. The 'generic' Micro SD card readers were 2 for 99p, whereas the Kingston Micro SD Card Reader was £4.99
The figures are quite revealing - the Transcend USB 3 reader that I paid around £10 for performs really well - well worth the money. The USB 3.0 Memory Stick in the USB 3.0 port is the best performer, as you would expect, but the Transcend is great for the money. The generic Micro SD readers are OK if you want to give someone a small text file, but if you want to move a big file, forget it.
In the past, I have actually run a Virtual Machine on a 64gb USB 3 stick in a USB 3 port - and it worked well.
Moral of the story - you DO get what you pay for when it comes to SD adapters - the 2 for 99p seem a bargain, but splash out a bit more the for a named brand.
Originally posted 29/Aug/2013