USB-C wire on a PC

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How can a tiny USB-C cable power my computer then display 2 monitors and a TV. It also has a keyboard and mouse and a camera. The USB-C is connected to a port then the port goes to all of the other devices. I know the port connects to the device but the computer still has to send data through that cable to all the other devices. It seems that everything would bottleneck through that cable. Thank you in advance to all those who post.

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2 Answers

Anonymous 0 Comments

USB-C cables look like a single thin wire, but can have up to 24 wires plus a shielding sheath.

https://pinoutguide.com/Slots/usb-type-c_pinout.shtml

But beyond the number of wires in the cable and their functions, USB-C is “smart” in that how and when signals are sent down the wires is also controlled by the USB protocol that is negotiated by the device at each end: the wire can emulate every protocol down to 1.1, but is designed to natively transfer signals compatible with USB 3.1 or higher.

To quote the page I linked above:
> The 24-pin double-sided connector provides four power/ground pairs, two differential pairs for USB 2.0 data bus (though only one pair is implemented in a Type-C cable), four pairs for high-speed data bus, two sideband use pins, and two configuration pins for cable orientation detection, dedicated biphase mark code (BMC) configuration data channel, and VCONN +5 V power for active cables.

Anonymous 0 Comments

All the devices end up bottlenecking into that one cable, but it’s moving too fast to make a difference. with enough devices you’ll reach a slowdown.

USB 2.0 had a max transfer rate of about 35 MB/s, about ten MP3 files per second. 3.0 went to 300 MB/s , or 85 songs, and 3.1 gen 2 or USB-C is 1.2 GB/s, or 342 songs, about ten times the speed over a decade ago. That’s enough to control several devices running full speed at the same time.

Power is different and separate, the hub is usually designed to provide power when the amount dedicated to the cable isn’t enough.

A hub with no power supply would be limited to the power output from the primary device it is plugged into, though that can be as high as 100 watts.