What does Thunderbolt Mean for the Mac?

In late February Apple announced a new line of MacBook Pros with a new interface, Thunderbolt. Now, just over 2 months later Apple has release it’s second line of products with Thunderbolt. However, there is still not a single Thunderbolt product on the market. So why is Thunderbolt such a big deal?


First lets take a look at what Thunderbolt is, and what it was designed to do.

Thunderbolt is Intel’s technology, but they partnered with Apple and the technology uses the mini display port that has been used on Macs for the last several years. This does not mean that all Macs have Thunderbolt, but existing accessories are backwards compatible.

Thunderbolt is an interface designed for connecting peripheral devices to a computer. Thunderbolt essentially combines PCI Express and DisplayPort into a new serial data interface that can be carried over longer and less costly cables. Because PCI Express is widely supported by device vendors and built into most of Intel’s modern chipsets, Thunderbolt can be added to existing products with relative ease.

The interface was originally designed to use flexible optical fiber cables, but a version using conventional copper wiring was also developed to furnish the desired 10 Gb/s bandwidth at lower cost. Intel’s implementation of the port adapter folds Thunderbolt and DisplayPort data together, allowing both to be carried over the same cable at the same time. A single Thunderbolt port supports hubs as well as a daisy chain of up to seven Thunderbolt devices; up to two of these devices may be high-resolution displays using DisplayPort.[5] Apple sells existing DisplayPort adapters for DVI, dual-link DVI, HDMI, and VGA output from the Thunderbolt port, showing broad compatibility.

General specifications
Length 3 meters maximum (copper)
Width 8.3 mm
Height 5.4 mm
Hot pluggable Yes
Daisy chain Yes, up to 6 devices
External Yes
Connector Mini DisplayPort
Signal 10 W
Bitrate 10 Gbit/s PCIe bi-directional
Protocol PCI Express, DisplayPort v1.1a

What will Thunderbolt be good for?
The first thing to understand when it comes to Thunderbolt, is that it’s a hight powered expansion port and not designed for small accessories. Thunderbolt is ideal for expansion. One of the major complaints about the Mac Pro was the lack of PCIe card slots. With Thunderbolt, six devices can now be attached to each port, all with the speed of PCIe. This likely means that the days of PCIe cards are numbered, and we’ll see device move external.

Keeping all of this in mind, Thunderbolt devices are not going to be cheap. For some time I don’t think we’ll see any devices on the market for less than $300. Thunderbolt is very exciting, but it will be for Pro users who need some serious accessories for their Macs. Think of it the same way that you would currently, Thunderbolt is for the same accessories that you would buy a PCIe card for.

Currently Thunderbolt is only supported on the Mac, with plans to be rolled out to PC’s next year. There will only be a limited number of items available for the next year as well. The Thunderbolt development is not done and we are likely to see many improvements including optical cable support so we can achieve long distances between our computers and devices

Does Thunderbolt replace USB 3.0?
No, Thunderbolt and USB 3.0 compliment each other. Thunderbolt devices are very different from USB. We don’t need to have a Thunderbolt based printed, USB 3.0 is plenty fast and more affordable. Also USB devices will be more common and more affordable. It’s exciting to still take advantage of 5Gbps. While there is not official USB 3.0 Support from Apple, CalDigit has developed USB 3.0 cards that bring USB 3.0 to the Mac. It’s also likely that when Intel support’s USB 3.0 next year Apple is likely to have USB 3.0 built in.