Question Connecting USB 3.0 hard drives to Thunderbolt ?

Mar 26, 2023
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I have several USB 3 hard drives (with USB Micro-B connectors). When I connect them to my laptop Type-A Superspeed ports, I get USB-3 speeds no problem. However, if I use an adapter to connect to the Thunderbolt ports, I only get USB-2 speed. Does the drive itself have to be Thunderbolt compliant or is it a cable problem? I have not been able to find an adapter that promises to maintain USB-3 speed into a Thunderbolt port.

This is an HP, Windows 11 laptop with Type-C Thunderbolt ports marked with the lightning logo.
 
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Paperdoc

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I found a really good article about this here

https://www.cablechick.com.au/blog/...MIkvTio4z6_QIVxZFbCh2u8gn_EAAYAiAAEgJiBPD_BwE

NOTE near the end there is a comment about the type of cable used. Some common USB Type C cables that do NOT include certain shielding types cannot support speeds any better than the old USB 2 system. The article does point out the markings commonly used on cables to help you find the right ones for the speeds you expect to use, and the limits on cable length that impact the performance.
 
Mar 26, 2023
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Yes, good article, thanks. It says "Thunderbolt 3 cables are ALWAYS USB-C to USB-C and are marked with the Thunderbolt logo and a "3" if they have 40Gbit/s support.. " This suggests that any adapters won't be compliant. My hard drives have the Micro-B connector so it's beginning to look like I can never get the full speed into Thunderbolt ports. Can that be right? It's very annoying!
 
Mar 26, 2023
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The drive doesn't have to be Thunderbolt compatible, because USB-C can switch between different modes depending on the controller. My question is if the specifications for the laptop explicitly states that USB-C port supports USB 3.x.
Understood. The ports are definitely described as "Thunderbolt", but I'll check if it's possible that it's also USB3.x
 
Mar 26, 2023
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The manual says the port will:
Connect an AC adapter that has a USB Type-C connector, supplying power to the computer and, if needed, charging the computer battery.
– and –
Connect USB devices, provide high-speed data transfer, and charge small devices (such as a smartphone), even when the computer is off.
NOTE:Use a standard USB Type-C charging cable or cable adapter (purchased separately) when charging a small external device.
– and –
Connect display devices that have a USB Type-C connector, providing DisplayPort output.
NOTE:Your computer might also support a Thunderbolt docking station.


Not sure what that's telling me!

However, laptopmag.com says
All Thunderbolt 3 ports are also USB Type-C 3.1 ports and use the Type-C's thin, reversible connector. You can connect any USB Type-C device to any Thunderbolt bolt, because technically, Thunderbolt is an "alt mode" for USB.
 
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The problem I have with USB-C is it's a physical connector standard. Everything else around it is optional, though I think the only thing you're really guaranteed with it is USB 2.0 functionality. So unless the specifications somewhere explicitly states the USB-C port can do it, I assume it can't.

But to see if there's something going on with the converter you have, have you tried plugging it into another USB-C port that is specified to support USB 3.x? If there's still an issue with it, I recommend getting another one from a reputable company like Anker (such as https://www.amazon.com/Adapter-Anker-High-Speed-Transfer-Notebook/dp/B08HZ6PS61 or https://www.amazon.com/Anker-Adapter-Converts-Technology-Compatible/dp/B01COOQIKU)

If you still run into issues, then I would chalk it up to that port somehow doesn't support USB 3.x. And to explain that bit, the pins used for USB 3.x are shared with Thunderbolt. So it could be possible they wired up those pins to a Thunderbolt-only controller
 
Mar 26, 2023
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Thanks - good idea to try the cable into a USB 3.x specified port. Mine is a cheap adapter, and Amazon and Ebay sellers bung the word "Thunderbolt" into their item titles very freely. I'm currently on a chat with HP support and they are being useless -asking "is the port damaged?", etc!
 

Paperdoc

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There are TWO different "Micro-B" connector systems. The one for USB 2 has five contacts inside a single shell, whereas the Micro-B SuperSpeed versions used for USB 3.2 has two groups of five contacts each, in a single shell that looks like it is sub-divided into two sections with a depression between them. Of those only the larger SuperSpeed one has all the lines necessary for USB 3.2 fast signalling. So, which type is the sockets on your USB 3 drives? IF they are the 2-section Superspeed ones they should be able to do the faster speeds.

You do need good cables and adapter, but the cables do NOT need to be the very fastest for Thunderbolt at up to 40 Gb/s. For use with a "laptop hard drive", the slowest speed USB 3.2 Gen1, at 5 Gb/s, is quite sufficient because the HDD itself cannot access and transmit data any faster. That is still 10 X what USB 2 can deliver!

Check also some details about power. The HDD's now sold as "laptop hard drives" CAN operate on the power available form a basic USB 3.2 port at 5 VDC with max 0.9 A current. They can NOT operate on less (not on a USB2 port, for example). From what O can see on Thunderbolt specs the port on your laptop should supply that. BUT I don't know about how your adapter makes connections. MAYBE it limits things, although inadequate power should NOT allow the HDD to function at all.

Consider getting a cable to go from your laptop Thunderbolt / USB 3.2 port to a USB Micro-B SuperSpeed port , something like this at 3 feet

https://www.amazon.com/AmazonBasics-Type-C-Micro-B-Gen2-Cable/dp/B01GGKYIHS/ref=sr_1_2?crid=27VUW54AJ9CX8&keywords=thunderbolt+to+usb3+micro-b&qid=1679885667&sprefix=thunbolt+to+usb3+micro-b,aps,92&sr=8-2

or even a shorter one.
 
Mar 26, 2023
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There's no problem with the drives (superspeed micro-B) or the cables I use to connect them to the laptop's Type-A superspeed ports (I get USB 3 speed). It's either the adapter I am using to go into the Thunderbolt port or the ports themselves. Will follow hotaru.hinu's suggestion today to see how the cable works into other laptops.
 
The manual says the port will:
Connect an AC adapter that has a USB Type-C connector, supplying power to the computer and, if needed, charging the computer battery.
– and –
Connect USB devices, provide high-speed data transfer, and charge small devices (such as a smartphone), even when the computer is off.
NOTE:Use a standard USB Type-C charging cable or cable adapter (purchased separately) when charging a small external device.
– and –
Connect display devices that have a USB Type-C connector, providing DisplayPort output.
NOTE:Your computer might also support a Thunderbolt docking station.


Not sure what that's telling me!
USB highspeed is usb 2.0
USB superspeed is 3.x
 
Mar 26, 2023
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Then the manual is nonsense, because it also describes the Type-A ports by saying "provide high-speed data transfer", and they are marked SS and definitely work at USB 3.x speeds.
 

Paperdoc

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Regarding the speeds of the CONNECTORS:

Type A connectors do come in different models for USB 2 and USB 3.2. Older USB 2 Type A has 4 contact strips on a plastic base in the connector, and the plastic now is coloured black. The new USB 3.2 version looks very similar except that the plastic is blue. HOWEVER, look closely inside and you will see FIVE additional contacts in the back of the connector. If the male connectors AND female sockets do NOT have those five extra contacts in them, they are not USB 3.2.

USB 3.2 now comes in three main versions or speeds (a faster is coming, MAY be called another version of 3.2 or maybe USB 4.) Gen1 is max 5 Gb/s data transfer rate, Gen2 is max 10 Gb/s, and Gen 2x2 is 20 Gb/s. The USB people say that a true USB 3.2 Type A connector is just fine for the slowest of those (Gen 1, 5 Gb/s) and MAY work of Gen2, but not guaranteed. You should be using the newer Type C connector system for Gen2, and MUST use them for Gen2x2. Now, there are not a lot of devices available that can actually supply data to a communication sybsystem at a rate exceeding 5 Gb/s. No mechanical hard drives (with spinning disks and moving heads) are that fast - not even high-performance desktop HDD's, never mind slower-performance "Laptop hard drives". SOME SSD's can deliver data over 5 Gb/s, but not over 10. So for use with a single laptop HDD, even a Type A USB 3.2 connector system SHOULD give you that Gen1 performance.
 
Apr 19, 2023
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Regarding the speeds of the CONNECTORS:

Type A connectors do come in different models for USB 2 and USB 3.2. Older USB 2 Type A has 4 contact strips on a plastic base in the connector, and the plastic now is coloured black. The new USB 3.2 version looks very similar except that the plastic is blue. HOWEVER, look closely inside and you will see FIVE additional contacts in the back of the connector. If the male connectors AND female sockets do NOT have those five extra contacts in them, they are not USB 3.2.

USB 3.2 now comes in three main versions or speeds (a faster is coming, MAY be called another version of 3.2 or maybe USB 4.) Gen1 is max 5 Gb/s data transfer rate, Gen2 is max 10 Gb/s, and Gen 2x2 is 20 Gb/s. The USB people say that a true USB 3.2 Type A connector is just fine for the slowest of those (Gen 1, 5 Gb/s) and MAY work of Gen2, but not guaranteed. You should be using the newer Type C connector system for Gen2, and MUST use them for Gen2x2. Now, there are not a lot of devices available that can actually supply data to a communication sybsystem at a rate exceeding 5 Gb/s. No mechanical hard drives (with spinning disks and moving heads) are that fast - not even high-performance desktop HDD's, never mind slower-performance "Laptop hard drives". SOME SSD's can deliver data over 5 Gb/s, but not over 10. So for use with a single laptop HDD, even a Type A USB 3.2 connector system SHOULD give you that Gen1 performance.
You are mixing up the decimals. 10gbps USB3 is 1GB/s and PLENTY of SSDs hit this mark. Gen2x2 (20gbps) is a special case that is rare-to-non-existant and requires specific support on both devices.
A standard SATA SSD runs about 5Gbps or 500MB/s, the speed of the USB3.1 interface.
THe 7000MB/s speeds we see advertised on the PCIe Gen4 NVMe SSDs are in fact 60-70gpbs. Over PCIe. Whcih is much faster than USB obviously.
 
You are mixing up the decimals. 10gbps USB3 is 1GB/s and PLENTY of SSDs hit this mark. Gen2x2 (20gbps) is a special case that is rare-to-non-existant and requires specific support on both devices.
A standard SATA SSD runs about 5Gbps or 500MB/s, the speed of the USB3.1 interface.
THe 7000MB/s speeds we see advertised on the PCIe Gen4 NVMe SSDs are in fact 60-70gpbs. Over PCIe. Whcih is much faster than USB obviously.
Most computer manufacturers use the 5Gbps flavor of USB 3.x since it's cheaper to implement with maybe one or two 10Gbps ports as few people have devices that go that fast.

Also PCIe 4.0 uses 128/130b encoding. So the actual raw bandwidth is closer to 74.88Gbps if we're talking about saturating a 4x link
 
Apr 19, 2023
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Most computer manufacturers use the 5Gbps flavor of USB 3.x since it's cheaper to implement with maybe one or two 10Gbps ports as few people have devices that go that fast.
Wrong.
Many many external SSDs reach 1GB/s or 10gbps. I have one myself, as well as a Gen2x2 one that runs at 1800MB/s (Gen2x2, 20gbps) attached to my WIndows machine but only 950MB/s (10gbps) when attached to my MBP.
Most USB3 ports these days are 10gpbs. Whether A or C. Gen2x2 is barely used and 3.1 (5gpbs) isn't enough.
 

Paperdoc

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From what I read, any SSD designed with a SATA interface is going to be limited by the max data transfer rate of the SATA communications subsystem. The fastest current version of these is 6 Gb/s, and many SSD's of that type can get close to that for actual data transfer rate on sequential reads. An NVMe design of SSD certainly can move data faster than that, particularly if its memory is suitably designed AND the interface uses most or all 16 of the possible data lanes of a PCIe interface. I see max transfer rates for the fastest such NVMe SSD's hittting 30 Gb/s, even faster than the max of the current USB 3.2 Gen 2x2 communication subsystem.

Then when I look at how a mobo USB3.2 Controller connects to the rest of the system, it appears this step requires that the limits of the external connecting cables have to be respected. Thus a Gen1 or Gen2 Controller is likely to use only ONE PCIe lane yielding max 10 Gb/s, and a Gen 2x2 Controller would up that to 2 lanes for 20 Gb/s max. Thunderbolt 4 (USB4?? to come??) does something similar and can achieve 40 Gb/s.

So it appears that NVMe type SSD's installed in a mobo M.2 slot with direct connections to the PCIe bus may be able to use MANY PCIe lanes and achieve those super speeds. However, any SSD of whatever type mounted in an external case and connected by cable to a USB 3.2 mobo Header and Controller will not be able to use as many PCIe bus lanes because the cable itself limits the max data rate. I understand that the Gen 2x2 system provides only 1 port (not 2) per Controller and uses the lines in the cable differently in order to achieve the 20 Gb/s data transfer max. (I think they are using differential signal lines as part of that.) As usual, the length of the cable for Gen 2x2 performance is limited. Thunderbolt 4 currently out-performs USB 3.2 Gen 2x2 and even emerging USB 4 with different Controllers, cables and software drivers.