This year at CES, we heard quite a bit about products coming out using USB 3.0 and/or Thunderbolt. Hard drives, card readers, monitors, even laptop docking stations. Thunderbolt is becoming more and more common in PCs, while the USB Promoter Group plans to update USB 3 in order for it to reach 10Gb/s, virtually eliminating the speed gap. Many devices come in one flavor or the other, but for some, you have a choice.
What's the Difference?
As of now, the primary difference between USB 3.0 and Thunderbolt is transfer speed, but there are other distinguishing features.
- Thunderbolt transfer speed is 10Gbps, while USB 3.0 is 4.8Gbps. As mentioned, USB 3.0 may be upgraded to 10Gbps, but Intel (the patent holder for Thunderbolt) is planning changes of their own. Soon we will see optical cables for Thunderbolt devices, which will increase the transfer speed to a maximum of 20Gbps.
- Thunderbolt can transfer up to 10 watts of power to devices, while USB 3.0 can transfer 4.5 watts.
- Thunderbolt cables tend to be more expensive. A three foot USB cable can be purchased for just over two dollars, while a comparably sized Thunderbolt cable will set you back close to $50.
- Thunderbolt doubles as a display connection. Out of the box, USB 3.0 doesn't support this. While DisplayLink has technology that will allow user to output a display signal to a monitor via USB 3.0, doing so requires additional hardware.
- Several Thunderbolt devices can be chained together, meaning several devices can connect to a single thunderbolt port. In order to do something similar with USB 3.0, a user would have to purchase a USB 3.0 hub. These aren't terribly expensive. In fact, you can buy one for less than the cost of a single thunderbolt cable.
- USB 3.0 ports are backwards compatible with all USB devices. That doesn't mean your old USB stick from 2003 will transfer at 4.8Gbps, but it will fit in the port and it'll work at normal speed. Thunderbolt is new technology, so the only devices it's backwards compatible with are those that use Mini DisplayPort (the predecesor to Thunderbolt, used only for display devices).
- Thunderbolt and USB 3.0 is available on all new Apple workstations (except the MacPro—ugh), and just about all new PCs have USB 3.0, but it's pretty rare to find Thunderbolt on a new PC.
Which do you Choose?
There are good arguments for both. Chose USB 3.0 if any of the following are true:
- Your computer doesn't support Thunderbolt
- You can't afford a Thunderbolt device
- There is no Thunderbolt equivalent device
- The device in question doesn't require fast transfer speeds. For example, don't buy a Thunderbolt mouse (not that one exists). Similarly, I doubt I'd ever buy a Thunderbolt printer, or headset. Primarily because they don't exist, but also because they just don't need the transfer speed.
Go with Thunderbolt if any of the following are true:
- You have a Thunderbolt capable workstation and you need superior transfer speed (as in, if you're a video editor working with high bit-rate footage). For example, if you plan on editing video off an external RAID, or if you need to connect several monitors to your laptop, the 10Gbps transfer speed will be nice. There are also external video capture devices that take advantage of Thunderbolts superior speed.
- You're connecting several devices to your workstation at once, Thunderbolt's ability to chain several devices together using a single port is very nice. You could use a USB hub, but you'd need three of them and three USB 3.0 ports to equal the potential of a single Thunderbolt port.
- You're a freak for minimalism. Having more than one cable going to your MacBook Pro is criminal, amirite?
The Bottom Line
For RAIDs, external HDDs and SSDs, video capture and playback devices, and external PCIe expansions Thunderbolt is the better option. USB 3.0 just can't match the speed (yet), and daisy chaining devices together is incredibly convenient. For just about everything else that's not a monitor, USB 3.0 is the way to go. Monitors are a different beast. Between HDMI, DVI, Dual Link DVI, DisplayPort, Mini DisplayPort, Thunderbolt and now USB 3.0, you have a lot of choices. Go with what fits your budget and your display port.
Mike Wilhelm is Videomaker's Content Director.