Thunderbolt technology

Thunderbolt and USB 3.0 explained

  • What is Thunderbolt and how fast is it?
  • Thunderbolt ports on Apple MacBook Pro laptops
  • How does USB 3.0 compare to Thunderbolt?

What is Thunderbolt?

Thunderbolt is a type of high-speed computer connection - for connecting peripherals and accessories, such as hard drives and monitors, to computers. Thunderbolt was formerly codenamed LightPeak, and was developed by Intel. It can carry data, video and power signals in a single copper cable. In the future, Thunderbolt cables may use fibre optics rather than copper, especially over longer distances.

Thunderbolt USB 3.0 Firewire speed comparison chart

Thunderbolt's 10Gbps maximum speed makes it twice as fast as USB 3.0

How fast is Thunderbolt compared to USB 3.0?

Thunderbolt has maximum theoretical data transfer speeds of 10 gigabits per second (Gbps). This is double the speed of its main rival, USB 3.0 (Superspeed USB), which transfers data at 5Gbps - itself more than ten times faster than a USB 2.0 connection. 

Thunderbolt is also 12x faster than Firewire. Thunderbolt, therefore, is at the cutting edge of transfer speeds, demonstrated by Intel’s claim that a full-length HD movie can be transferred via Thunderbolt in under 30 seconds.

Where will I find Thunderbolt?

The first computers to feature Thunderbolt ports are Apple’s latest range of MacBook Pro laptops - including 13,15 and 17-inch models. Thunderbolt compatibility is actually integrated into the existing Mini-DisplayPort connector but you can tell the difference because a lighting bolt symbol has been added. Although Apple has collaborated with Intel to bring the first Thunderbolt-compatible computers to market, other manufacturers are set to launch their own devices in the future.

Is Thunderbolt compatible with DisplayPort and PCI Express?

DisplayPort is a digital display interface used to connect computers to monitors, designed to replace DVI and VGA connectors. It's most common on Apple and Dell computers. Thunderbolt combines DisplayPort and PCI Express protocols, so a single Thunderbolt connection could transfer both data, HD video and eight-channel audio signals simultaneously. Thunderbolt is therefore an ideal solution for dealing with professional-standard audio and video. Thunderbolt connections will work with DisplayPort monitors, but will need a cable adaptor.

Thunderbolt port on Apple MacBook Pro

Apple's MacBook Pro is the first computer to include a Thunderbolt port

How many devices can I connect with Thunderbolt?

Devices can be daisy-chained from a single Thunderbolt port - up to six data devices in total, or one display and five data devices.

When can I buy a PC with Thunderbolt?

Currently Apple is the only manufacturer offering computers with integrated Thunderbolt ports, after it launched its updated MacBook Pro range on 24 February 2011.

In contrast, USB 3.0 devices are already available from a variety of manufacturers. Apple’s MacBook Pro range also still includes Firewire and USB 2.0 sockets.

What devices can be connected with Thunderbolt? 

There are no devices yet which are designed to use the full data transfer rates that Thunderbolt allows. As it’s backwards compatible, however, monitors which use the Mini-DisplayPort connector can use Thunderbolt ports. Big names such as LaCie and Western Digital are signed up to produce Thunderbolt devices, but no launch dates have yet been announced.

Do I need Thunderbolt?

If you don’t need the fastest possible data transfer rates that Thunderbolt offers, then USB 3.0 will be perfectly fine, as well as being backwards compatible with USB 2.0, so all your USB 2.0 devices should still work, although at the lower speed.

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