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Thunderbolt vs UsbC
- Thread starter zoran
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Normal Thunderbolt ports can supply up to 15W of power. I verified by connecting my MacBook Air to the back ports on the Mac Studio (M1 Max).
They are not PD ports.
USB-C is a physical connector type.
Thunderbolt is a protocol that can use the USB-C connector, and can support a variety of interfaces including video and transfer speeds up to 40Gbps.
USB 3.1 Gen 2 is the protocol supported over the front USB-C connectors on the Studio Max. It can support speeds up to 10Gbps.
^^ There is a very simplified comparison between the two, there are more nuances of course!
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As I understand there are 3 thunderbolt buses/controllers built into M1 Max so the ports on the front are shared with one/two of those.
As M1 Ultra is two M1 Max you get double the buses and hence all six are thunderbolt 40Gbs ports.
I feel the question you should be asking yourself is why do you care and what are you planning to plug into them that could be of benefit.
Everything to do with Thunderbolt is expensive. Just take a look at external TB drive costs compared to USBC.
USBC is slower, but much cheaper.
10Gbps vs 40Gbps. That's the difference. You're barely going to notice a difference for the majority of devices. Need more lanes to make everything 40Gbps, which is why the Max doesn't have TB in the front and Ultra does.
Most SATA SSDs top at 5-6Gbps (550Mbps) and well within the 10Gbps limit. It's not until you're dealing with NVMe and multi-bay RAID solutions where you're really looking for 40Gbps. Even then, you can usually daisy-chain or use a TB hub (like the CalDigit Element Hub) to add some more ports. You're not increasing the available lanes, but rarely is the CPU/processing overloaded or saturated with true 40Gbps needs across everything where it would become an issue. Those that know it is an issue are already going Ultra or waiting to see what AS Mac Pro has.
Most SATA SSDs top at 5-6Gbps (550Mbps) and well within the 10Gbps limit. It's not until you're dealing with NVMe and multi-bay RAID solutions where you're really looking for 40Gbps. Even then, you can usually daisy-chain or use a TB hub (like the CalDigit Element Hub) to add some more ports. You're not increasing the available lanes, but rarely is the CPU/processing overloaded or saturated with true 40Gbps needs across everything where it would become an issue. Those that know it is an issue are already going Ultra or waiting to see what AS Mac Pro has.
More expensive to include the Thunderbolt protocol, and not as many people/devices that can take advantage of it. Which is why you only see it on the higher-end devices.
The whole USB-C spec is complete mess, throw Thunderbolt into the picture and it makes it worse. Unless a USB-C cable is properly labelled you don't know what you are getting? Is it a charging cable? Is it a power delivery cable? Is it a USB-C 3.x or USB-C 4 cable?
That's just regarding file transfer speed, you're leaving out the real major difference: video. Thunderbolt can support embedded video protocols, up to 6K60 in macOS.
I have yet to see one place where I can see all the differences between USB-C and Thunderbolt and all the various cabling options in one place. You get bits a pieces from different sources. No wonder why a lot are confused including me at times.
For cables, keep this image handy. Unfortunately it doesn't include TB4, but basically those are "do all" cables. TB4 would be on the far right, and have dots in each box, for all lengths.
That's still all about bandwidth. DisplayLink and other similar USB compressed video streams will get there, eventually for video/display. Usually the tradeoffs are not worth it. The compression technology to achieve is usually fairly CPU intensive and usually has artifacts visually. Basically trying to cut the data stream to 25% of what it should be. Exactly why driving monitors over USB and using USB-based docking stations is an issue, especially compared to TB.
The USB-C connector (via DisplayPort Alternate Mode) can also do 6K60 if DisplayPort 1.4 plus DSC is used. This is how [most] people are running the XDR on Windows machines.
When it comes to video, one crucial difference between USB-C and Thunderbolt 3/4 is that USB-C can carry one DisplayPort signal per port whereas Thunderbolt can carry two per port (going all the way back to Thunderbolt 1), enabling e.g. two independent monitors to run from a single Thunderbolt port using a hub or dock or "dual-link SST" monitors such as the LG UltraFine 5K and Pro Display XDR (if DSC isn't available) to run at full resolution and refresh rate.
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To make matters worse, the USB-C cable that comes with Macs these days only supports USB 2.0.
I would like to see USB die solely because of the mess they've made of the naming convention.
I know. But joking aside — what comes after USB? It’s been around for 25 years.