Difference between USB 2.0 and 3.0 Cables

December 21, 2015 by Editorial Team

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.

Definitions

USB 2.0 Cable

USB 2.0 vs 3.0 Cables
A diagram of a USB 2.0 pinout

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 nameWire colorDescription
1V-BUSRed or OrangePower of +5 volts
2D-White or GoldData –
3D+GreenData +
4GroundBlack or BlueCommon return path for electric current
  • USB 1.x/2.0 mini/micro pinout
Pin #Pin NameWire ColorDescription
1V-BUSRedPower of +5 volts
2D-WhiteData –
3D+GreenData +
4IDN/ADistinguishing cable ends (A plug (host):B plug (device)
5GroundBlackCommon 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.

USB cables matrix
USB cables matrix

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

A diagram of a USB 3.0 pinout
A diagram of a USB 3.0 pinout

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 NameWire ColorDescription
1V-BUSRed+ 5 volts power
2USB 2.0 Data-WhiteUSB 2.0 Data –
3USB 2.0 Data+GreenUSB 2.0 Data+
4GroundBlackCommon return path for electrical current
5USB 3.0 Transmit-PurpleSuper speed transmitter –
6USB 3.0 Transmit+OrangeSuper speed transmitter +
7Ground DrainN/AGround for signal return
8USB 3.0 Receive-BlueSuper speed receiver –
9USB 3.0 Receive+YellowSuper 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.

USB 2.0 Cable vs USB 3.0 Cable

What’s the difference between a USB 2.0 cable and USB 3.0 cable? 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.

Comparison Chart

USB 2.0 CableUSB 3.0 Cable
4-5 pinouts9 pinouts
Less expensiveMore expensive
Offers a maximum speed of 480 MB/sOffers a maximum speed of 5 GB/s
Preferably 5 meters in length or lessPreferably 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)

Video

Here is a video you can refer to for a simple explanation of USB 2.0 and USB 3.0 cables.