Why aren’t motherboards mostly USB-C by now?

There's no reason to replace USB A on most desktops since it would break 20+ years of backwards compatibility without any real benefit. Maybe 1 or 2 would be useful.

So, much as I hate to admit it, the real reason for this is bandwidth. Lets look at the best case scenario without dipping our toes into server grade hardware. AMD CPUs tend to have more I/O bandwidth allocated than Intel, so we'll take the top of the line desktop AMD CPU as of right now, the Ryzen 9 7950X (technically the X3D version is the actual top of the line, but that makes certain tradeoffs and for our purposes in this discussion both chips are identical).

On paper, the 7950X has 24 PCIe 5.0 lanes, and 4 on board USB 3.2 ports on its built in USB controller. So already we could have a maximum of 4 type-C ports if we had no type-A ports, however in practice most manufacturers opt to split the difference and go with 1 or 2 type-C ports and the remaining 2 or 3 ports as type-A. You can have more USB ports of course, but you need to then include a USB controller on your motherboards chipset, and that in turn needs to be wired into the PCIe bus which means taking up PCIe lanes, so lets take a look at the situation over there.

We start with 24 PCIe lanes, but immediately we're going to be sacrificing 16 of those for the GPU, so really we have 8 PCIe lanes. Further, most systems now use NVMe M.2 drives, and NVMe uses up to 4 PCIe lanes at its highest supported speed. So we're now down to 4 PCIe lanes, and this is without any extra PCIe cards or a second NVMe drive.

So, now you need to plug a USB controller into your PCIe bus. USB 3.2 spec defines the highest supported bandwidth as 10 Gbps. PCIe 5.0 defines the maximum bandwidth of a single PCIe lane as a bit over 31 Gbps. So the good news is, you can successfully drive up to 3 USB 3.2 ports off a single PCIe 5.0 lane. In practice though USB controllers are always designed with even numbers of ports, typically 2 or 4. In the case of 4, one lane isn't going to cut it, you'll need at least 2 PCIe lanes.

I think you can see at this point why manufacturers aren't in a huge rush to slap a ton of USB type-c connectors on their motherboards. With a modern desktop there's already a ton of devices competing for limited CPU I/O bandwidth. Even without an extra USB controller added in it's already entirely feasible to come dangerously close to completely saturating all available bandwidth.

USB A is still really common, especially for plug in peripherals...

Am I throwing away all my mice, keyboards, DAC, digital pens, and other peripherals just so I can have a connector with more bandwidth than I'll ever need? Nah.

Am I buying them or adapters all over again just so I can be compatible with a new universal standard that I don't need? Double nah.

KVM switches, or breakout hubs that these devices plug into, then a single USB c device goes to the computer is the most logical avenue for a migration. But this will take a long time. Most people don't even have that kind of luxury.

Usbc connectors are expensive and more difficult to drive. Usb-a connectors are cheap and easy to drive

I agree most motherboards should at least come with 2 or 4 USB-C ports.

That being said, people upgrading all their peripherals happens significantly less often than the PC upgrade itself, and 90% of my current setup relies on USB type A, so if a motherboard (specially mATX) needs to decide what ports to fit into limited space, I'd prioritize USB A for sure.

How the heck is USB-A a legacy port and what would I do with 11 USB-C ports on a PC when everything I plug into it besides my phone (depending on the cable) has a USB-A connector? Like how would I even use something as simple as a flash drive or Bluetooth/wifi/radio transmitter?

USB-C makes a ton more sense for mobile devices, docks, and charging, but not so much when you're plugging them into a suitcased size brick that doesn't move. I could see useful applications for something powered that needs a lot of bandwidth, but PCs also come with dedicated ports for all those peripherals too.

Because there is no reason to have more than 1 or 2 since almost everything uses a type A connector.

Most desktop peripherals are still USB-A. For low-power, low-data things like keyboards and mice, what would be the point of USB-C? It would increase the cost of the product but provide no real benefit to the user.

Also, if you had a new desktop motherboard with say 6 USB-C ports, would you expect all of them to be capable of delivering 20V at 5A so they can be used to drive USB-C monitors &etc? Because that's a lot of power to be running across your motherboard, even if you have a power supply that can handle it. You'll need a separate cooler just for the USB-C bus controller, and pray that nothing ever goes wrong with power delivery because it will probably fry the whole board.

Standard USB type A ports are cheaper, and more importantly, STURDIER then USB C ports. This is extremely important for peripherals that do not need to be disconnected and reconnected often.

USB C is great for convenience for certain things, but it's a weaker port in terms of physical connection strength.

I don’t understand why I would want a bunch of usb c ports? On a phone where there obviously isn’t space for a full sized port sure, but I find that fiddling with the one usb c port on the back of my desktop is a pain in the ass and the port really struggles to keep a good connection when attached to a stiff or heavy cable.

Would make much sense. You still want USB-A ports for most peripherals as using an usb-c port to connect a single mouse would be pretty much wasting a port.

However adding a Thunderbolt4 port or two along side the usual USB-A ports would be nice.

USB-C is very hard to manufacture and expensive as fuck as a result.

thats why.

Especially when most devices don't need the bandwidth or power needs of USB-C.

I'd honestly love to see everything USB-C-ified. Would be great to finally just have one standard to concern yourself with.

This is about cost. The standard USB ports are far cheaper and they probably already have a billion of them on hand. Plus all the board layouts already use standard USB for their layouts. Also you're not really getting any advantage from the USB c size wise or performance wise.

Further more now you'd have to make USB c to whatever form cables and make customers buy these new cables.

If u had to choose between 2 computers and 1 made u buy completely new cables for every peripheral which would u buy?

Weirder is that you can’t really find usb c mice and keyboards, though I really don’t know why.

This was written in 2021. Is it still true?

You could at the same time ask: "Why are motherboards no longer made for 486DX?". The answer is simple: Time and technology moves on, and USB-A is old.

My kids laptop has 4 IIRC. Getting a PC motherboard with more than one on rear and one connector for front of case was impossible last I looked. I generally keep my pc’s for about 5 years and wish to future proof somewhat. It is beyond ridiculous at this point. Although, I haven’t tried to buy one for a few months so perhaps this has changed.

I would like to see a new USB form factor for chonky hardware like desktop PCs that combines the sturdiness and reliability of USB-A with the symmetry and power delivery of USB-C

Had the same feeling a year and a half ago, I was thinking that maybe as I was not on a next gen CPU I was just on an older model and that's why it was not very present. I only have one usb-c on my motherboard B550M Micro ATX

my thinkpad has two usb-c ports, both can be used for charging. i still prefer usb-a cuz i still use peripherals and drives i have right now. im not ready throw them away for the sake of "newer ports."

Because USB C is just a fad

I like USB A for thumb drives and other legacy equipment but I definitely prefer more USB C. Right now, I have a connected to my laptop through it, one for charging and then 2 USB A for peripherals. I'd personally trade the other two USB A and use a small hub instead so I can charge my phone, watch and vape without a separate charger.

Where does L4SBot pull data from? R*ddit?

bandwidth and room on the board mainly

Btw, why is full ATX / full-size PC still that common, mATX / ITX almost rare? Only techy users or gamers add maybe a 4x ethernet card or a GPU and that's it; one PCIex16 slot would suffice. Better sound cards, wifi etc, are now almost always USB/-C or Bluetooth, if not already on the board.

Why is the time of slim-size desktop PCs still not there?

Article is two years old. I wonder if it’s still relevant, especially after the EU standardization change

I'm still on the Ryzen 5xxx platform and there aren't a lot of motherboards that have USB-C either unless you go high end like the ASRock Taichi.

Definitely need the ports though given how ubiquitous USB-C is nowadays.