Most USB users have some knowledge about USB 2.0 and USB 3.0, and that’s mostly their differences in transfer rate. The question is the ‘how’ and the ‘why’, and simply knowing how the two cables work will surely provide an answer to that question.
USB 2.0 Cable
USB 2 being released in early 2000, it was meant to add a higher transfer rate than the USB 1.x, and indeed it runs at 480 MB/S. Although USB 1.x does have a disadvantage with its performance, the cables however appear the same with four pins on a standard pinout and five on a mini or micro pinout.
- USB 1.x/2.0 standard pinout
|Pin #||Pin name||Wire color||Description|
|1||V-BUS||Red or Orange||Power of +5 volts|
|2||D-||White or Gold||Data –|
|4||Ground||Black or Blue||Common return path for electric current|
- USB 1.x/2.0 mini/micro pinout
|Pin #||Pin Name||Wire Color||Description|
|1||V-BUS||Red||Power of +5 volts|
|4||ID||N/A||Distinguishing cable ends (A plug (host):B plug (device)|
|5||Ground||Black||Common return path for electrical current|
Cables will also have different combinations of plugs on each end, whether it may be an A-type or B-type plug. You can refer to this table matrix for different plug combinations.
Aside from different plug type combinations, you should also know that having this certain kind of cables can only do so much with their length and that’s why a USB 2.0 cable has a preferred maximum cable length at 5 meters or 16.4 feet.
You can grab a USB 2.0 cable with A-Male and B-Male plugs at 4.8 meters or 16 feet for around $4.80.
USB 3.0 Cable
The 3rd version of the USB (Universal Serial Bus), it provides more enhancements like your superfast transfer rate of up to 5 GB/s. The newer version however, the USB 3.1. can go for up to 10 GB/s transfer rate. Take note, these enhancements will not take effect unless the cables are USB 3.0 capable, that’s because the new cable contains not only 4 or 5 pinouts but 9.
- USB 3.0 standard pinout
|Pin #||Pin Name||Wire Color||Description|
|1||V-BUS||Red||+ 5 volts power|
|2||USB 2.0 Data-||White||USB 2.0 Data –|
|3||USB 2.0 Data+||Green||USB 2.0 Data+|
|4||Ground||Black||Common return path for electrical current|
|5||USB 3.0 Transmit-||Purple||Super speed transmitter –|
|6||USB 3.0 Transmit+||Orange||Super speed transmitter +|
|7||Ground Drain||N/A||Ground for signal return|
|8||USB 3.0 Receive-||Blue||Super speed receiver –|
|9||USB 3.0 Receive+||Yellow||Super speed receiver +|
You can distinguish a USB 3.0 cable by simply identifying its blue color. The number of pins on each end can also be an identifier, by having more pins than your standard 2.0 cables. The preferred maximum length of a USB 3.0 cable is at 3 meters or 9.8 feet. This is to avoid data transmitted to cause data loss and corruption.
You can grab a USB 3.0 cable with A-Male and B-Male plugs at 3 feet for around $9.00.
There are quite a few technical and physical differences that are notable, one being how fast the data is transmitted. USB 2.0 can handle a transfer rate of 480 MB/s but with USB 3.0, you can go as high as 5 GB/s or even 10 GB/s with USB 3.1. These differences however will only take effect as long as you use the required cables for your ports. A USB 3.0 port can only use USB 3.0 cables to be effective, but USB 2.0 ports can use both USB 2.0 and USB 3.0 cables. However, the performance will fall back to 2.0 rather than 3.0. The same is true for your USB 3.0 port using a USB 2.0 cable. It is possible but the performance will still fall back to 2.0.
One key difference between the two cables is their pinouts. A USB 2.0 can only have as many as 4 or 5, but a USB 3.0 has 9. This is one of the main reasons a USB 3.0 cable can offer much more transfer rate than your USB 2.0. The cables of a USB 3.0 will also tend to be slightly thicker because of having more wires inside it, and can only reach 3 meters to be effective. That being said, it will also cost more.
So to sum up, a USB 3.0 cable contains more wires, thus offering more transfer rate. With more wires in it, it will also need more pinouts than your USB 2.0. And finally, USB 3.0 cable is backwards compatible, but as long as a USB 2.0 port or cable is in use, even though your system can handle a USB 3.0, the performance will always be with your USB 2.0’s performance.
|USB 2.0 Cable||USB 3.0 Cable|
|4-5 pinouts||9 pinouts|
|Less expensive||More expensive|
|Offers a maximum speed of 480 MB/s||Offers a maximum speed of 5 GB/s|
|Preferably 5 meters in length or less||Preferably 3 meters in length or less|
|Compatible with USB 3.0 port (As long as connector is compatible)||Compatible with USB 2.0 port (as long as connector is compatible and will have USB 2.0’s performance)|
Here is a video you can refer to for a simple explanation of USB 2.0 and USB 3.0 cables.