Is USB 3 fast enough to supply a 4K file?

OK, so the 'you can run three 4K monitors if you want to' thing is kind of like car maker's MPG statistics, but I can't really see a circumstance where you'd need to run three 4K monitors day to day, or how you'd be able to have them all on a desk anyway. One 4K TV on the wall as a preview screen, two say 27" 2560*1440 monitors to work on. Can anyone see a use case where that wouldn't be enough? There's no real case for 4K computer monitors to use at desktop working distance anyway because they would be far beyond the 'retina screen' barrier - I can barely see the dots on a 1.4k screen at any useful distance as it is.

The point of 4K is to be 'retina screen equivalent' at big screen TV viewing distances (say ten feet). Who uses a desktop computer screen that's ten feet away from them? What do they use it for?

Bitching that it can't realistically do something that realistically nobody will need it to do anyway seems to me a bit of a pointless exercise.

Fair point. The only time being able to drive 3 4k screens I can think of would be at a concert or conference and even then you'd probably be using considerably cheaper projectors anyway.

Just did some Googling - USB 3 apparently tops out at 635MB/s. For an uncompressed 4k movie file, you're looking at ~478MB/s.

If all those Thunderbolt ports are used for the 4k displays where will the data come from? It also needs those thunderbolts to store the data or have I missed something?

USB3 might be good enough to feed a compressed 4K stream though (say H.265 MP4).

Jon

USB3 might be good enough to feed a compressed 4K stream though (say H.265 MP4).

Jon

“By combining 20Gbs bandwidth with DisplayPort 1.2 support, Thunderbolt 2 creates an entirely new way of thinking about 4K workflows, specifically the ability to support raw 4K video transfer and data delivery concurrently,” says Jason Ziller, Marketing Director for Thunderbolt at Intel. “And our labs aren’t stopping there, as demand for video and rich data transfer just continues to rise exponentially.”

Professionals and enthusiasts alike will be able to create, edit, and view live 4K video streams delivered from a computer to a monitor over a single cable, while backing up the same file on an external drive, or series of drives, simultaneously along the same device daisy-chain. Backing up terabytes of data will be a question of minutes, not hours. And finally, since Thunderbolt 2 is backwards compatible, original investments in cables and connectors continue to pay off while supporting dramatically improved performance. Thunderbolt 2 is currently slated to begin production before the end of this year, and ramp into 2014.

Given the nature of USB 3, I doubt if it'll manage the same.