What is the difference between USB 2.0 and USB 3.0
By Koder at Thu, 01/07/2010 - 13:48
There is a new standard in the USB world called USB 3.0, in this article we will discuss the difference between USB 2,0 and USB 3.0. Universal Serial Bus or USB, as you all know is the most popular connection standard between devices and a host controller (usually located on a computer). USB has undergone many revisions and the latest USB hardware spec to come out is version 3.0, after version 1 and 2. Everything from your flash drives, mice, keyboard, PDAs, Game Consoles, GPS chargers, cell phone connectors and chargers, GPS devices and bluetooth head sets all use USB in one form or the other. So lets see whats the differences between the most popular USB 2 and just out USB 3 standard are
Let me begin by saying that USB 3.0 is a major advancement over USB 2.0, far greater in impact than what USB 2 was over USB 1.0 . The biggest difference is the speed at which it can communicate with the computer's host controller and the biggest advantage is that it can maintain a backwards compatibility with USB 1 and 2.0. USB 2 had a maximum speed of 480 Mbps, which was great at that time but now it might not be enough because we now have USB thumb drives that are 64 GB in size, cell phone and PDAs that have a lot of internal storage built in, and even at 480 Mbps a full transfer of data in between devices can take a long time. In comparison to this, USB 3.0 boasts a maximum transfer speed of 4.8 Gbps yes, 4.8 Giga bits per second, almost 10 times faster than USB 2.0. Even with realistic numbers you can transfer data between your computer to a 64 Gigabyte thumb drive to full capacity in under 20 minutes!
Faster speed is not the only difference, power usage and requirements for USB 3 devices are much "greener". The USB 3 devices will provide more power when needed to the device to achieve a maximum throughput and conserve power when the device is connected but is idling. Modern operating systems such as Windows 7 already has support built in for USB 3.0 and Mother Board manufacturers already have the USB 3 port built in on the upcoming motherboards. The USB 3 port on a motherboard is characterised by a blue color (see the two images below showing USB 2 and USB 3 ports).
USB 3 in comparison to USB 2 can communicate its latency potential to the host which results in a better transfer performance, better asynchronous transfers are also going to improve communication between devices. The better transfer rates allow high bandwidth intensive devices and applications such as Hi Def Video streaming, Digital Video recorders etc a perfect candidate for USB 3.0. In comparison to other technologies, USB 3 leaves eSATA as well as Bluetooth protocols far behind in terms of speed and performance. Although there are not many USB 3 devices out there yet, but it will clearly become the standard in this new year 2010. Major operating systems vendors have already incorporated and embraced the standard, the good thing is the backward compatibility will not let your existing USB 2 devices go obsolete for another few years