Comparing USB 3.0 and Thunderbolt
Despite Intel’s insistence that their high-speed connection technology Thunderbolt is not competing with the third version of Universal Serial Bus, we cannot help but compare the two connecting standards that found its way to computers and other digital devices within the same span of time.
Thunderbolt is mostly associated with Apple products, found on at least a dozen devices with more coming out soon as confirmed by Intel. Windows PC would also use the high-speed interconnect at the end of 2012. The upcoming Windows 8 has already demonstrated that it can support Thunderbolt.
USB, meanwhile, has been enjoying its success as one of the most successful interfaces in the history of personal computers. Almost all PC and peripheral devices have adopted USB. More precisely, the USB installed base is more than 10 billion units while still growing at more than 3 billion annually. With this in mind, it seems impossible for any interconnect technology to replace USB.
The truth is that both Thunderbolt and USB have come from the same hands as the latter is also co-developed by Intel. The company states that Thunderbolt should work as a complement to USB instead of competing with it. But why would you use a slower interface if a faster one exists?
The Thunderbolt’s throughput is 10 Gbps while USB 3.0 is at 4.8 Gbps. That can translate to downloading a 25 GB HD movie in 30 seconds using the Thunderbolt port as compared to 75 seconds through USB. Thunderbolt can also deliver power of up to 10 Watts while USB 3.0 can handle only up to 4.5 watts.
The Thunderbolt specification contains two protocols: PCI Express (PCIe) and DisplayPort. The Thunderbolt controller chip switches between the two protocols to support varying devices. DisplayPort offers HD display support as well as eight channels of HD audio. A Thunderbolt connector has two full-duplex channels; each is bi-directional and capable of the 10Gbps of throughput.
While the Thunderbolt interface looks good in paper, most experts agree that there is no need for it yet. The very high bandwidth would be useless unless a computer’s internal drive can handle it which is currently not the case. The fastest throughput of an internal drive is only 6 GBps (SATA III) and that is coming from the latest solid state drive. A Thunderbolt external drive connected to a laptop will still follow the 6 GBps bandwidth and not the prescribed 10 GBps.Continued on the next page