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Why aren't motherboards mostly USB-C by now? (2021)

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Re: Why aren't motherboards mostly USB-C by now? (2021)

#181

Post by [deleted] »

arcticbull wrote: post #176
userbinator wrote: post #154

My experience has shown that USB C connectors are far more fragile than A, and every time I plug one in, for some reason the fit just feels vague and unsatisfying. An A plug, when you get it the right way, slides in solidly. As others have mentioned, C seems to have been designed to be the smallest possible, which makes sense for mobile devices, but not for a desktop and its peripherals.

Interestingly enough, they're specced the opposite way. > Standard USB has a minimum rated lifetime of 1,500 cycles of insertion and removal, the Mini-USB receptacle increased this to 5,000 cycles, and the newer Micro-USB and USB-C receptacles are both designed for a minimum rated lifetime of 10,000 cycles of insertion and removal. [1] > To accomplish this, a locking device was added and the leaf-spring was moved fro…

[deleted]

Re: Why aren't motherboards mostly USB-C by now? (2021)

#182

Post by tentacleuno »

stephenr wrote: post #173
crote wrote: post #67

Earlier quoted context omitted.

Just don't accidentally stick USB-C into a USB-A port. It will fit and it will short the port, causing the machine to crash. Speaking from experience...

While you're at it, also don't accidentally plug a computer's Ethernet port into an rj45 wall plate that connects to an analogue pabx, it will fit and it will fry the NIC. Don't put shit in the wrong hole is really one of the most basic lessons we should teach people in life.

On my computer, the USB-C port is at the back -- one time, I shorted the motherboard out due to trying to insert a USB-C cable without looking. Only did it once, but learned my lesson.

Re: Why aren't motherboards mostly USB-C by now? (2021)

#183

Post by picture »

arcticbull wrote: post #176
userbinator wrote: post #154

My experience has shown that USB C connectors are far more fragile than A, and every time I plug one in, for some reason the fit just feels vague and unsatisfying. An A plug, when you get it the right way, slides in solidly. As others have mentioned, C seems to have been designed to be the smallest possible, which makes sense for mobile devices, but not for a desktop and its peripherals.

Interestingly enough, they're specced the opposite way. > Standard USB has a minimum rated lifetime of 1,500 cycles of insertion and removal, the Mini-USB receptacle increased this to 5,000 cycles, and the newer Micro-USB and USB-C receptacles are both designed for a minimum rated lifetime of 10,000 cycles of insertion and removal. [1] > To accomplish this, a locking device was added and the leaf-spring was moved fro…

I think it's a bit ironic that the cable is considered more costly than the receptacle, which is generally true if you consider the device as a whole, but now we have multiple hundreds of dollars thunderbolt cables and the cap on the actual receptacle component is below $10 even for ones with support for higher speeds.

But then again, most people don't have the SMD rework tooling to be able to easily replace receptacles

Re: Why aren't motherboards mostly USB-C by now? (2021)

#184

Post by stephenr »

nubinetwork wrote: post #78

Find me a device that needs the bandwidth of USB type C. The only thing that springs to mind are 4k HDMI capture cards...

M2 SSDs can already saturate even a Thunderbolt port; then there's the alt-mode uses like DisplayPort, or the tunneling in usb4 that essentially gives thunderbolt3 functionality, such as running PCIe devices.

Re: Why aren't motherboards mostly USB-C by now? (2021)

#185

Post by 0x38B »

Retr0id wrote: post #109
abhinavk wrote: post #32

Earlier quoted context omitted.

Weirdly, the port on a cheap mechanical keyboard I have is USB-C but the cable they packaged is USB-C -> USB-A instead. They likely didn't package C->C because of the chicken and egg problem. Not everyone has enough Type-C ports.

Type-C hubs are annoyingly expensive, because they all assume you want all the USB 3.x speed and/or power delivery bells and whistles - but for connecting simple peripherals none of that is necessary. I built my own based on a USB 2.0 hub IC, but I never got around to publishing the design files. I should get on that! Even building a single prototype unit cost me about the same as a single off-the-shelf type-C hub, b…

I was outraged when I couldn’t find a small, simple USB 2.0 USB-C hub for my Framework! (1)

1: the four USB-C ports it provides aren’t enough for my use; one is occupied by Apple’s USB-C DAC (the Framework’s 3.5mm port is unusably noisy with my Shure IEMs). Then add my charger, tethered iPhone, and a peripheral like a mouse or drawing tablet, and you can see why I need a hub.

P.S. if you did release the files and it was a reasonably affordable DIY project (e.g some soldering and assembly), I’d love that. Although I guess you’d need to buy a fair number of all the components to bring the price down.

Re: Why aren't motherboards mostly USB-C by now? (2021)

#186

Post by [deleted] »

picture wrote: post #183
arcticbull wrote: post #176

Earlier quoted context omitted.

Interestingly enough, they're specced the opposite way. > Standard USB has a minimum rated lifetime of 1,500 cycles of insertion and removal, the Mini-USB receptacle increased this to 5,000 cycles, and the newer Micro-USB and USB-C receptacles are both designed for a minimum rated lifetime of 10,000 cycles of insertion and removal. [1] > To accomplish this, a locking device was added and the leaf-spring was moved fro…

I think it's a bit ironic that the cable is considered more costly than the receptacle, which is generally true if you consider the device as a whole, but now we have multiple hundreds of dollars thunderbolt cables and the cap on the actual receptacle component is below $10 even for ones with support for higher speeds. But then again, most people don't have the SMD rework tooling to be able to easily replace receptac…

[deleted]

Re: Why aren't motherboards mostly USB-C by now? (2021)

#187

Post by silon42 »

hughesjj wrote: post #113
eurleif wrote: post #77

Earlier quoted context omitted.

>because they would, together with a common USB C cable, allow creating the forbidden USB A to USB A cable Not hard to do this regardless. Amazon sells A-to-A cables[0]; and Unicomp keyboards for example have a USB-A port in the back, and connect to PCs with a bundled A-to-A cable. Seems like preventing this is a lost cause. [0] https://www.amazon.com/Monoprice-1-5ft-24AWG-Cable-Plated/dp...

I have more USB switches and kvms that do a-a instead of a-b than I care to admit

Yeah, USB switch for keyboard/mouse is the reason I expect to be using USB-A (or the "illegal" adapter) for few decades more.

Re: Why aren't motherboards mostly USB-C by now? (2021)

#188

Post by stephenr »

TheRealPomax wrote: post #76

A lot of devices don't need what USB-C offers: USB-A is a concurrent, not legacy, standard. You want USB-C for high-power, high-transfer-speed connections. An incredible number of peripherals don't need either of those things, connecting them with USB-C just makes no sense.

Usb4 does not define "type-a" connectors, thus type-a by definition is not "concurrent" with type-c in the usb spec. It is deprecated/legacy (ie still in use but not supported by newer versions of the spec)

Re: Why aren't motherboards mostly USB-C by now? (2021)

#189

Post by dwaite »

amelius wrote: post #106
lxgr wrote: post #99

Earlier quoted context omitted.

USB does use error detection (CRC), but if you transfer enough data over anything, you'll eventually see undetected errors.

If this is true, then the MTBF design parameter is unacceptably low.

It is rated maximum 1 bit error per 10^12 bits, which makes the chance of enough errors within a single packet to break the CRC (or to cause more than 3 retries) astronomically small.

Re: Why aren't motherboards mostly USB-C by now? (2021)

#190

Post by picture »

arcticbull wrote: post #178
aslilac wrote: post #3

calling USB A “legacy” and a “relic” is so misplaced. we all still own USB A devices. I challenge the author to go find a wired keyboard or mouse that comes with a USB C plug. it’s possible, but not easy. the thing is, we could just have both! this isn’t some winner/loser scenario. the real question should be why these computers with enough bandwidth for 11+ connectors don’t at least split the difference with 6/5 of…

USB A was released in 1996, it's older than I suspect the majority of HN readers at this point. An A to C cable is entirely passive, so not exactly a big deal to get a cheap adapter. Not sure I'd rely on keyboards as the standard bearer for 'not a relic' many of them still support PS/2 via passive adapter. That was announced in 1987 and is older than me.

Comparing technology to human lifetimes doesn't seem very relevant. Even not accounting for broad categories like "fire" or "language", we're still using individual technology from "long ago" like knives, forks, pen and paper, etc. It's fine to make improvements that keep backwards compatibility (more ergonomic scissor should be able to cut the same paper), but changing connector just because it's old is unwise.

The issue of type C is that it's trying to accommodate the entire spectrum of applications from very high bandwidth to very low cost. The range of possibilities has much increased since when Universal Serial Bus was devised, thus many recent solutions feel like they're bad at everything and good at nothing. Perhaps we should allow the specialization of type A as a cheap, reliable, slow, high power, connector, and save type C for only when high throughput is needed?

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