Today, let's learn about the difference between USB 2.0 and USB 3.0, the charging speed of USB 3.0, and whether it is backwards compatible with USB 2.0.

Since its release in 2000, USB 2.0 has been used in many devices: computers, tablets, mobile phones, cameras, storage devices, televisions and even Bitcoin miners. In the past decade or so, it has gained tremendous popularity, and its successor USB 3.0 has also been rapidly promoted on new devices.

The difference in transmission speed between USB 2.0 and USB 3.0: In theory, USB 2.0 can transmit speeds up to 480Mbps, while USB 3.0 has a transmission limit of 5000 Mbps. This indicates that USB 3.0 has a transmission speed at least 10 times faster than USB 2.0. But we all know that these numbers have little meaning unless they are the results of real testing.

According to test results from TweakTown, NETWorkWord, and The New York Times, the speed of USB 3.0 is 2.5 to 3.5 times faster than that of USB 2.0. Although this is not in line with theory, three times the speed is still considered a significant improvement.

To verify this, we conducted speed tests on USB 3.0 and USB 2.0. Connect the Toshiba Cuvio USB 3.0 external hard drive to an idle desktop computer and measure its transmission speed using CrystalDiskMark. We first connect it to the USB 2.0 port and record its speed, then repeat the process using the USB. 03 port. The following are the results of the speed test:　　

The results show that the transmission speed of USB 3.0 is 2.5 times that of USB 2.0, which is consistent with the test results of TweakTown, NETWorkWord, and The New York Times.

However, many people have not noticed that not all devices benefit from the transmission speed of USB 3.0. External hard drives and flash drives will be able to fully utilize USB 3.0 to improve transmission speed, and USB 3.0 phones and tablets can also increase transmission speed by 2-3 times. However, for other USB devices such as external optical drives, keyboards, mice, cameras, printers, speakers, network adapters, etc., there is almost no significant difference between USB 2.0 and USB 3.0.

USB 2.0 and USB 3.0 interfaces: Color is the key to distinguishing between USB 2.0 and USB 3.0. Under normal circumstances, the USB 3.0 interface is blue, while USB 2.0 is black or white, as shown in the following figure:

Are USB 2.0 and USB 3.0 compatible?

USB 3 is backwards compatible, so the short answer is yes. The specific formula can be seen as follows:

USB 2.0 port+USB 2.0 device=USB 2.0 performance

USB 2.0 port+USB 3.0 device=USB 2.0 performance

USB 3.0 port+USB 2.0 device=USB 2.0 performance

USB 3.0 port+USB 3.0 device=USB 3.0 performance

Any combination is effective, but to maximize the functionality of USB 3.0, you need the following three devices to be used together: USB 3 ports, USB 3 devices, and USB 3 cables.