external hard drive-Thunderbolt2 or USB3?

JMR wrote:

Thanks. I have the specs but have seen some different discussions about how much an external hard drive can take advantage of T2 transfer speeds vs USB3.

JAH1924 got his speeds a bit wrong.

For the record

Thunderbolt 2 . 20GB/s

Thunderbolt 1 . 10GB/s

USB3 . 5GB/s (rising to 10 soon)

The fastest drives around do not exceed 4-5GB/s

JMR wrote:

Does T2 offer an advantage over USB3 for an external hard drive connected to an iMac 5K?

What about original Thunderbolt vs. USB3?

I’ll play devil’s advocate here. Thunderbolt is another technology Apple (and Intel by proxy) is promoting that the rest pf the PC industry is lukewarm about. It is very analogous to Firewire, a technology Apple also pioneered but has recently abandoned in favor of Thunderbolt. A lot of users were burned by Apple dropping support for Firewire. Well, we do have a Thunderbolt-to-Firewire adapter that kinda works. USB 3.0, on the other hand, has quickly become the industry standard. While technically not as fast as Thunderbolt, USB 3.0 is ‘good enough’ for general purpose use. Thunderbolt is much more than a hard drive interface and professionals will probably prefer it.

If it were me, personally, I would use USB 3.0 for my external hard drive needs. It’s more flexible and will work on just about any PC it is connected to.

Thunderbolt 1/2 will be faster, but also consider whether you would want/need to connect your external drive to other Macs without Thunderbolt ports or indeed Windows-based PCs. USB3 would present greater flexibility perhaps?

Actually, Thunderbolt 2 has a transfer speed of 20 GB per second. Thunderbolt 1 has a transfer speed of 10 GB per second and USB 3 has a transfer speed of 5 GB per second.

Hi

Thunderbolt 2 is a transfer speed of 10GB/s, thunderbolt 5GB/s and USB 3.0 2.5GB/s

Some more info here :

https://www.apple.com/uk/thunderbolt/

If you want a single (spinning) disk you won't have any advantage with TB except paying at least double the amount.

Describe the use scenario of the external disk (backup, video editing…).

it's only if the external hd is a ssd or hybrid that the interface speed could be a limiting factor

internal Raid 0 with 2 hard drives (Lightroom images)

This will give you a max of 400MB/s

USB 3 and TB 1 can handle that fine.

And let's not forget that the forthcoming 3.1 revision will increase the speed to 10Gb/s