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USB-C is about to go from 100W to 240W, enough to power beefier laptops

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Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#381
post #156

Earlier quoted context omitted.

Can you explain the differences between them? I don't have many USB-C devices (Switch and MacBook) but wouldn't you be able to use the most "fully featured" cable for every scenario?

The most "fully featured" cable with a USB-C tip is often like <0.5m long.

And $40+. Buying a long one for a music recording interface (that sweet sweet I/O) was super painful.

I guess it's cheaper now but in what world is a $50 cable to power an accessory reasonable in any way.

Source: https://www.sweetwater.com/c1225--Thunderbolt_Cables

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#383
post #284

Earlier quoted context omitted.

The Nintendo Switch can be bricked if you use the wrong cable, although my understanding is that it's not built to the USB-C spec: https://www.reddit.com/r/NintendoSwitch/comments/87vmud/the_... Either way, this is an incredibly common device that can be damaged by incompatible hardware where it's difficult to determine compatibility without bricking the device.

> Either way, this is an incredibly common device that can be damaged by incompatible hardware where it's difficult to determine compatibility without bricking the device. This is 100% Nintendo's fault for using the USB-C connector type but not actually bothering to adhere to the USB-C specification.

Exactly. If you're going to base your interconnect on an industry standard, you have two options as far as I'm concerned:

A) Follow the spec

B) Make your off-spec interconnect physically incompatible with standard devices

Going off-spec with a compatible and physically indistinguishable connector is an "attractive nuisance," to use the tort term.

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#384
post #280

Does there exist a device that you can plug in USB and HDMI cables and have it tell you what features, modes, etc that cable supports? Seems like having something like that wouldn't eliminate all the problems but would make them easier to deal with by quickly identifying that the cable you tested is or is not appropriate for the task at hand. That aside, I'm looking forward to running my laundry room off of a dozen U…

If you just want to know if a usb cable can safely delivery a certain current, then a cheap multimeter might do. If you want to test whether a cable will work with a certain protocol at a certain data rate, just plug it in and see if it works. Because the alternative method[1] costs hundreds of thousands of dollars. [1] https://www.keysight.com/ca/en/products/bit-error-ratio-test...

This seems absurd. Is there a reason why Microsoft can't build a feature into Windows that tells you what USB spec a cable is using? (And details like transfer speed, power, etc.)

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#385
post #346
post #279

Earlier quoted context omitted.

It should be impossible for any set of non-damaged, non-defective, spec-compliant set of USB-C cables and peripherals to cause fires. The specifications are very carefully designed to prevent any combination of cables and devices from causing damage.

> It should be impossible for any set of non-damaged, non-defective, spec-compliant set of USB-C cables and peripherals to cause fires. That is a fairly significant list of conditions. As an example, I have encountered significant heating in a damaged power cable on the original power supply of a laptop from a reputable vendor. It's easy to argue the owner should immediately replace the damaged power supply, yet many…

I find it a bit disconcerting that we're talking about delivering 240 W over a cable that consumers are unlikely to differentiate from a 15 W cable (i.e. USB-C specification) or even from a 2.5 W cable (e.g a USB cable they would have used fifteen years ago).

Yes, exactly! It’s foolhardy.

And maybe unnecessary -- haven’t Apple just shown that you can get amazing performance with very low power requirements? And shouldn’t we all be trying to minimize power usage, to try to reduce CO2 emissions, mining of rare and toxic elements, plastic waste, etc etc etc?

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#386
post #11

I look forward to USB 4.1a Type C.2 Phase iii.b Gen 3E and the 482646282 different cable capability combinations that all plug in and have no distinction of those capabilities whatsoever. I also look forward to all the necessary and helpful posts telling me how the identical ports on my laptop are in fact diffferent despite their identical appearance. But at least everything uses the same plug, so that’s nice.

Will people ever stop complaining?

If it started making physically different cables or sockets to add new features, people whine how nothing is compatible anymore and if it stopped adding new features to stay compatible, you call the standard dead and not forward thought.

Instead it's gradually upgrading the standard with the same physical socket, so that at least some compatibilities are kept and it's still moving forward.

Can it be better than that?

A bit of confusion on which version you need is better than not being able to plug it in at all.

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#387
post #274

Earlier quoted context omitted.

Of the 415 pages in the spec, 8 of them are devoted to arc mitigation in the "USB PD High-Voltage Design Considerations" section. Lots of discussion about detecting unplug and limiting slew rates. In practice that will cost pennies to implement and will therefore be skipped in many designs. ("I got a great deal on this charger on Amazon!") Time to develop some user superstitions around USB C: "The withdrawal velocity…

I have already enough talk with my family to explain which charger and cable goes to which phone. Even more humiliating is them looking at me as if I was complete idiot after me suggesting to them that the selection of cable itself may be cause of their problems. They had some physics at school and from their point of view the cable is just a bunch of copper and it should absolutely make no difference for how fast th…

> They had some physics at school and from their point of view the cable is just a bunch of copper and it should absolutely make no difference for how fast their phone charges.

Even if it is just a bunch of copper, there is thin and long copper and thick and short copper. I had a cheap, long micro-USB cable that was too thin to deliver 2A at 5V, my phone couldn't charge correctly. Using the Ohm's law, I could calculate that the voltage drop was enough to get it out of specs.

The cables you need to transport power at 5V can be surprisingly thick, and that's a reason why fast chargers are usually higher voltage. I ran the calculation to power a 5V LED strip over 10 or so meters, and came to the conclusion that I would have needed utility-sized cables.

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#388

Earlier quoted context omitted.

GPUs in gaming laptops use WAY more power than even the hungriest mobile CPU. Strong mobile CPUs like the Ryzen 5800H are usually in the 45W ballpark while mobile RTX 3080 class GPUs can go as far as 170W+ and that is still half of what the desktop equivalent can draw.

What's the cooling situation on such a laptop?

Depends on the laptop. Can't do really big statements.

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#389

Earlier quoted context omitted.

Or! We could go one step further, and change the connector to make sure that people use them correctly. Wouldn't that be clever!?

Better: add a color band to the connector. One line for low power, two for medium, three for high.

The problem is you have:

Power: 18W, 30W, 45W, 60W, 100W, 240W

Data: No Data, 480Mbps, 5Gbps, 10Gbps, 20Gbps, 40Gbps

You also have a potential variety of modes that could influence your ability to achieve those speeds with certain devices.

Re: USB-C is about to go from 100W to 240W, enough to power beefier laptops

#390

Earlier quoted context omitted.

GPUs in gaming laptops use WAY more power than even the hungriest mobile CPU. Strong mobile CPUs like the Ryzen 5800H are usually in the 45W ballpark while mobile RTX 3080 class GPUs can go as far as 170W+ and that is still half of what the desktop equivalent can draw.

What's the cooling situation on such a laptop?

Depends on the laptop.

Don't search for the ASUS G14, the G14 is dead when plug too much power into it. Bold statement, but I've warned you. You need power, your going to hear the fans. There's currently no solution for cooling it quietly.

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