I feel it is important to mention that active thunderbolt cables can only be used with thunderbolt hosts/peripherals and cannot be used with USB 3.x devices at all*. However, given the specialty nature of TB3 active cables I don’t think it’s really necessary to label them as such, it should be fairly obvious even from the size of the connector (extra length/space for the active components). Also, thunderbolt cables without the 3 should be assumed to only support 20 Gbps, the label of 3 should guarantee 40 Gbps speed. This is another way to infer if a cable is active or passive.
All high performance type C cables (more than 3A, 5 Gbps or faster) need an e-marker chip, so it should really be a feature of all host devices to enumerate functionality of the attached cables. However I believe a wall charger is considered the host and the phone/tablet/laptop is considered the peripheral.
E-marked cables handle the negotiation. Non marked cables depend on the host, which may disable the port when an incorrect configuration is detected or which would be damaged when attempting this (see: USB A to A cables)
Algal, HDMI requires license fees and Displayport does not (or is just cheaper, feel free to Google the exact pricing schemes). Displayport in dual mode devices (sometimes labeled DP++) is compatible with HDMI using a passive adapter, otherwise an active adapter is needed.
Displayport has consistently been a better, newer, even future-proof standard so if there is any quality concern it would be on the limitations of HDMI to your Displayport signal (that is without digressing into the various compression schemes both use). Making the real question: why does anyone use HDMI at all?
This was discussed over on slashdot a couple of years back. There was a memorable post from one of the wags over there which may help in cable ID…
“When you plug a cheap offbrand charging cable into your device, the USB-C standard signals this by emitting a blue flash and burning your device to a crisp. This feature has proven less popular with users than was at first envisioned.”
I’m not sure what you’re actually requesting here. TB1 and TB2 don’t use USB-C connectors, so there can be no confusion between versions 2 and 3.
Any TB cable (indicated with the lightning icon) with a USB-C connector will be version 3 or 4, whether or not there is a number printed on it. And a passive cable can deliver 40Gbps, if it is short enough.
For computer use, one key advantage is audio support. I have a Dell display that includes conferencing features (camera, microphone and speakers). Although a USB connection is required for the computer to access the camera and microphone, it will deliver HDMI audio to the speakers, which is very convenient in my situation, where I’m only using the speakers (I’m using a different device for camera/mic) and therefore haven’t connected its USB ports.
The connectors perhaps. But we will still be dealing with standards such as DP and HDMI (and their limitations) because of the way USB-C alt mode works for likely many more years.
Thanks Glenn. I definitely took a few steps forward in my understanding of USB connections as a result of your article. But I readily admit, I’ll need to read it a couple more times to feel at all comfortable in this confusing arena.
Maybe a current issue facing me, if you have time, will help me better understand the speed limitations of the data transmission protocols vs any inherent limitations posed by the different ports and cables.
I upgraded our internet plan from an advertised 100 Mbps to 600 Mbps. But I’m still getting around 90-100 as before. Comcast made a service call and tells me all is well at the line drop outside our house.
So not wanting Comcast to touch our computer rack. LOL I was told so my our network guy. I decided to check the speed myself right after their modem. The Comcast rep said the problem is probably wifi or the router but I’m skeptical. So I did the following to add an additional speed test to the ones I’ve been running on my computer and iPhone either over WiFi and ethernet connections
Now the USB issue…
I have a MacBook Air that has two (2) Thunderbolt 3 ports using USB-C ports.
I found I had a USB-C to Type A connector and I also had an Apple Type A to Ethernet adapter. I built that chain and connected the ethernet cable to the Comcast modem.
And… I got the same speed; around 90-100 Mbps.
My question is… By connecting these adapters in between the MBA and the modem am I limiting the speed or should that connection be capable of 600Mbps if Comcast is delivering it?
As you can probably tell, I’m still not totally understanding what determines any speed limitations be it the cable, port or type of protocol being used.
The Apple USB-Ethernet adapter is limited at 100 Mbps. You need the TB2-Gigabit adapter to get 1 Gbps. Or any of these inexpensive type-A models such as this one.
Unless you’ve got a truly high-end computer with a wired Gigabit (or faster) Ethernet connection and corresponding Ethernet switches, you’re not likely to experience that 600Mbit/s speed on a single device.
Where that connection will work best is (assuming your router and Wi-Fi solution are up to the task) will be when you have multiple devices hitting your network at once. You can have multiple devices sucking down bandwidth (think each family member streaming HD or 4K video on their respective devices) without saturating your external link.
Of course, if you have a fast computer with a wired Gigabit connection to your router, then let the good times roll.
I have to semi-disagree. Most computers sold in the last several years have gigabit Ethernet. Gigabit Ethernet switches (for 4 to 8 ports) are very cheap. 802.11ac and later routers and even most 802.11n routes including gigabit switches built in and some have 2.5 Gbps uplinks. iPhones and iPads can manage 100s of Mbps over appropriately fast Wi-Fi.
I would say there are few times that your computer or mobile device needs to lean on over 100 Mbps individually, as you note. But with large downloads or uploads, Internet-based backups, and iCloud Photos syncing, I can see speeds > 100 Mbps at times.
Yes, although you might want to get a mini-dock with other features, like pass-through power, Type-A ports, and video ports if you’re adding Ethernet. This Anker mini-dock looks fairly slick and I’m generally a fan of Anker products.
Yeah, there’s plenty of inexpensive options with extra USB-A ports, video, and in such a case you probably also want power passthrough so you can also charge your Mac.
This a couple decent examples. Note the MOKiN doesn’t support 60 Hz 4K.
I have made a video that’s pretty dense (my first outing of this kind) about USB and Thunderbolt compatibility, ending with an explanation of why the Thunderbolt 4/USB4 cable is the best you can get for the least amount of compatibility worries.
Oh, that’s funny. When embedded, I think it drops in my overlay image, which is an A for Aperiodical. It doesn’t appear on YouTube. Maybe there’s a configuration settings I missed.
First… I have desperately wanted a standard USB/connection status app for years. Apple and Microsoft should really have this built-in by now. It would be a simple UI showing ports, devices and any signal errors or anomalies that might indicate a faulty cable or device connection with easily identified color and indicators. Advanced users could optionally enable more detailed info as needed.
Second… A suggestion for anyone when buying a new USB adapter:Check all the connections with non-critical devices and data in the first 14-30 days (before the return window closes). For example, I have found many popular adapters may not work after the computer sleeps unless you physically unplug and re-plug them. Ethernet ports seem to be the biggest offender. This includes adapters from Belkin, Cable Matters, UGREEN, etc. No matter the brand, there is always a chance you got one of the defects in a mass produced batch.
Be sure to put your Mac/Windows system to SLEEP with the adapter connected via Ethernet or with a USB storage device that does not have crucial data on it. See if it is functional after you WAKE the system (especially desktops). Also, try a large single file copy (ie. use a big installer file). I even gently wiggle the connector part-way through the transfer to check for weak connectors.
Even with these checks, you may encounter the occasional “slow-death” adapter.
I have a Cable Matters ethernet + 3 USB adapter that slowly deteriorated. The ethernet port initially worked after sleep/wake, but it had to be plugged in more slowly over time to work correctly (as if I was moving in slow-motion). After 1.5 years the ethernet status lights come on, but no data transfer happens until I unplug and slllooooowly re-plug the device 2-3 times and check connectivity. I can switch between this faulty CM adapter and a working USB device, and the other one will work no matter how I slam it into that same computer port. …sigh… The CM adapter is now just a spare for emergencies and never used with a sleepy computer.
and DVD 
players, where Displayport was made for computers 
and their monitors so their needs and goals didn’t fully overlap (For example, I think 99% of people are not concerned about people pirating their spreadsheets). Thankfully we are now seeing a convergence as “smart” TVs have apps & chips in them, and more people consume media on their computers. Hopefully USB will replace all these other connectors.
LOL I was told so my our network guy. I decided to check the speed myself right after their modem. The Comcast rep said the problem is probably wifi or the router but I’m skeptical. So I did the following to add an additional speed test to the ones I’ve been running on my computer and iPhone either over WiFi and ethernet connections
