Intel's Thunderbolt: What you need to know (FAQ)

For now Intel's breakneck input/output technology can only be found in one computer line, but other devices will soon follow. Here's what it's all about and when you can use it.

Josh Lowensohn Former Senior Writer
Josh Lowensohn joined CNET in 2006 and now covers Apple. Before that, Josh wrote about everything from new Web start-ups, to remote-controlled robots that watch your house. Prior to joining CNET, Josh covered breaking video game news, as well as reviewing game software. His current console favorite is the Xbox 360.
Josh Lowensohn
4 min read
Thunderbolt logo

Intel's long-awaited Light Peak technology, now known formally as Thunderbolt, is finally available on its first consumer device, and the company today unveiled more details about when we'll be seeing it in consumer PCs and gadgets.

First unveiled at the Intel Developer Forum back in 2009, the data transfer tech promises to replace a handful of ports with one that can do more things, and do them faster.

Its first inclusion in a computer is in Apple's MacBook Pro line, which refreshed earlier today with Thunderbolt ports across the line (see CNET's hands-on here). Intel followed up a few hours later with a press conference about the technology, as well as its plans to bring it to computers and devices over the next year or so.

To help readers better understand what the technology is and why it matters, CNET has put together this FAQ.

What is Thunderbolt?
Thunderbolt is Intel's new input/output technology that promises to bring transfer speeds that exceed what is currently available with USB 3.0, as well as extending that speed across several devices at once. In terms of where you'll see it, Thunderbolt will appear as a new port on laptops and PCs, as well as on devices that support it.

Intel unveils Thunderbolt (photos)

See all photos

The technology itself makes use of existing DisplayPort and PCI-Express data protocols to open up what you can do with a single port into multiple uses and at high speeds. This includes "daisy chaining" up to seven Thunderbolt-equipped devices together, while retaining full speed across all of them at once.

How fast is it?
Thunderbolt currently runs with a top speed of 10Gbps. Since there are two wire pairs, and the system is bidirectional, a single cable can have up to 40Gbps coursing through it at its maximum theoretical capacity (20Gbps upstream and 20Gbps downstream). Intel says that those speeds will one day top 100Gbps in data throughput when it moves from a copper wire to optical fiber. In the interim, copper wire has both speed and cable length limits, keeping cable length at 3 meters or less. The data transfer is also bidirectional, meaning it can both transmit and receive data at the same time, and at its top speed.

During Intel's press conference about the technology this morning, the company demonstrated it working on a MacBook Pro, pulling four raw, uncompressed 1080p video streams through a Thunderbolt storage array, and feeding into a Thunderbolt-attached display, all the while topping more than 600MBps in its transfer speeds. An earlier test of just file transferring had gotten it up to 800MBps.

To put this in perspective of what's been available up to this point, that's twice as fast as the theoretical limit of USB 3.0, 20 times faster than USB 2.0, and 12 times faster than FireWire 800.

Here's a demo from this morning's Intel press conference that gives you an idea of what it's capable of in a video editing and viewing work flow, as well as a file transfer:

Watch this: Introducing Intel's Thunderbolt

When can I get it?
The long and the short of it is that you can get Thunderbolt today, so long as you buy Apple's MacBook Pro, which is the first laptop to ship with a Thunderbolt port as a standard port across its entire line.

As far as it arriving on PC laptop and desktop machines, the company today estimated that we wouldn't see it there until early next year given OEM design cycles. In the interim, there will be a slew of Thunderbolt-ready devices like hard drives and displays that will take advantage of the technology arriving in the spring. One of the first will be a LaCie external hard drive called the Little Big Disk that packs multiple solid state drives in a single enclosure that works with Thunderbolt.

Will I be able to add it to my old PC or laptop?
If your old machine is a PC you built, replacing its motherboard with one that will carry Thunderbolt will do the trick. During Intel's press conference today, the company stayed mum on offering it as an expansion to PCs through PCI Express slots, or laptops through ExpressCard technology.

Thunderbolt cables, which look just like Mini-DisplayPort cables.
Thunderbolt cables, which look just like Mini-DisplayPort cables. Intel

Does this replace USB?
Intel is positioning Thunderbolt as an "adjacent" technology, one that will complement it. That said, USB's ubiquity means it's not going anywhere just yet. Intel has also said it plans to support USB 3.0 in future chipsets alongside Thunderbolt.

How much will it cost?
Intel has stayed mum on cost besides saying that it was competitive with other high performance I/O solutions. As far as its inclusion in the new MacBook Pros, it's been added as a standard feature across the entire line, versus being a paid add-on at the time of configuration.

The same cost principle goes for Thunderbolt's cables too. Because Thunderbolt is not an open specification, that means companies cannot simply make their own through a license, though that could change once we're into the lifespan of the product.

Updated at 12:08 p.m. PT on 2/25 with additional information on total speed per cable.