New computers have now been coming with USB 3.0 ports for years. But just how much faster is USB 3.0? Will you see a big speed improvement if you upgrade your old USB 2.0 flash drives? USB 3.0 devices are backwards compatible with USB 2.0 ports. Theyll function normally, but only at USB 2.0 speeds. The only downside is that USB 3.0 devices are still a bit more expensive. Theoretical Speed Improvements USB is a standard and defines maximum signaling speeds for communicating across a USB port. The USB 2.0 standard offers a theoretical maximum signaling rate of 480 megabits per second, while USB 3.0 defines a maximum rate of 5 gigabits per second. In other words, USB 3.0 is theoretically more than ten times faster than USB 2.0. If the comparison ended here, upgrading would be a no brainer.