More on the Thunderbolt cable availability front

More on the Thunderbolt cable availability front

Summary: According to industry insiders, there's no crisis in finding Thunderbolt cables, despite my personal experience of the other week. But the cables may remain specialty items for a while.


According to industry insiders, there's no crisis in finding Thunderbolt cables, despite my personal experience of the other week. But the cables may remain specialty items for a while.

Last week I recounted the trouble I had finding a cable for my new 4TB Thunderbolt array. The shrink-wrapped package had to be walked from the back room of a local Apple Store after some consultation among the sales staff.

Several readers and developers contacted me with some thoughts on the cables.

These Thunderbolt cables aren't the run-of-the-mill cables we're used to. Currently, I understand that there are third-party cables undergoing qualification, however, the cost of the cables will remain high, according to a video engineer who declined attribution. He said that each cable is individually trimmed and calibrated to guarantee 10-Gbps throughput.

Several readers said that they had sighted Thunderbolt cables on shelves in various retail settings, such as Frys and various Apple retailers. One reader suggested that there had been a run on the cables shortly after the technology's introduction and various technical managers and developers had purchased the cables whether they had a Thunderbolt peripheral or not.

There was the suggestion that the cost of Thunderbolt cables was in-line with other high-speed cables such as external Mini SAS (Serial Attached SCSI) and Infiniband, both of which have been available for years now. Now, I can understand the high cost of these cables, which are used by specialty, high-performance applications. But Thunderbolt?

The whole point of Thunderbolt is to leapfrog slower performance from "consumer" technologies like USB 3, which is now branded as "SuperSpeed USB." One or more Thunderbolt ports can now found on millions of Macs in the wild, but it appears that peripheral vendors are moving slowly and letting the market grow.

The Thunderbolt PHY is the same as a mini DisplayPort PHY. But the cables aren't the same. My MacBook Pro uses the Thunderbolt port as a mini DisplayPort for video out, you can plug in a mini DisplayPort adapter that translates to other video standards such as DVI, HDMI or VGA.

However, this isn't necessarily making the after-market situation around cables any clearer. The video engineer believes that there is still a lot of confusion about Thunderbolt cables.

A Thunderbolt cable cannot act as an mDP cable. An mDP cable cannot act as a Thunderbolt cable. Many no-name dongle suppliers say their HDMI or DVI or VGA adaptors are Thunderbolt compatible. They are merely mDP compatible.

According to Apple Support documents, there are restrictions on getting power from a Thunderbolt cable to a device, and where you can connect a display in the chain. It's an echo of the termination issues with SCSI that dogged us in the early days of the Mac.

Only the device directly connected to your Mac can get power from the Thunderbolt port. The rest of the devices in the chain must be powered by separate power adapters.

A DisplayPort device can be part of the chain, but it must be at the end. For example, if you want to connect both a Thunderbolt hard disk and a DisplayPort display to your Mac, connect the display to the hard disk and then connect the hard disk to your Mac.

On several discussion boards, I noticed a reports of problems when connecting multiple adapters into the Thunderbolt chain, such as going from a mini DisplayPort to DVI adapter to a DVI extension cable and then to a DVI to HDMI adapter. Yet another third-party cable opportunity, it appears.

Topics: Hardware, Mobility, Networking, Telcos

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  • Hmm

    The cable has active chips in either end to help control and guarantee the 10Gb bandwidth..why would you want to rely on a cheap $1 (USB 2.0 480Mbps) - type cable for your 10Gbps speeds and reliability? Me no thinks a cheap butt cable makes sense with high speed data paths.. the higher the frequency.. (i.e. 1Gb vs 10Gb).. the more expensive the technology, including cables.

    The Thunderbolt PHY is same as the 10Gb Ethernet PHY not the DisplayPort PHY... remember, 2 different technologies, PCIe and DisplayPort, DisplayPort cannot handle data.

    Thunderbolt is not targeted at USB 3.0 and consumer, it is directly positioned for the professional and prosumer level of customer, specifically in applications like professional video editing, graphics, etc.
    • The problem...

      is that Mac's with a Thunderbolt port or ports are being purchased by the lay person, not necessarily the prosumer. Also, Thunderbolt devices are taking much longer to come to market and are priced much higher than USB 3.0 devices. Even devices that allow connection of Thunderbolt Macs to USB 3 and eSATA devices are rare. In my opinion, going with Thunderbolt and not also including USB 3 was a poor decision on Apple's part.
      • Ivy Bridge

        I'm guessing that Apple will be including USB 3.0 support once they switch over to Ivy Bridge later this year. Don't expect them to move away from Thunderbolt, however. The TB port likely means that they can drop the Mac Pro while still providing support to those who need access to PCIe cards (since TB supports external expansion boxes).
  • Sheesh, Try they have just about any cable you want and

    Sheesh, Try they have just about any cable you want at very high quality and cheaper than 99% of other outlets.

    When I want one I usually buy much longer than I need and at least two because they are so inexpensive.
    • Still does not have TRUE Thunderbolt cables

      I have used too. Very inexpensive. BUT their "Thunderbolt" cables are really only relabeled Mini DisplayPort video cables. They are not for hard drives and other hardware, yet.
  • A few corrections

    The Apple tech note may have an error.

    Devices that can daisy-chain must provide power; otherwise the cables (or DisplayPort dongles) won't work.

    The situation is different with the Apple Thunderbolt Display. You are guided to connect the captive cable to the Thunderbolt port on your computer, and connect other devices to the built in Thunderbolt port of the display.

    If you use your own cable to connect the display's Thunderbolt port to your Mac, and then try to use the captive cable to connect to a device that requires power (like the Sonnet ExpressCard adapter or Seagate's GoFlex Portable adapter or El Gato's SSD drive), they won't work.

    If you connect any of those devices to other Thunderbolt peripherals that have 2-ports for daisy-chaining, they work as expected.

    As for cascading several different dongles and should expect problems as there will be serious degradation of the high-speed signaling.

    USB 3.0's highest data rate has always been called Super-Speed. Still confusing, when comparing to High-Speed, Low-Speed, and Full-Speed. I'll leave it to others to explain how these terms are easy to remember. Personally, I likes Sony's S100, S200, and S400 designation for IEEE-1394, and Apple's FW400 and FW800 for the same.

    Thunderbolt? Embrace it for what it does, or use an alternative for what it doesn't. With Z77 motherboards with native USB 3.0 going public this week, there are plenty of alternatives for the budget conscious, though the future might be the Z77 motherboards with both Thunderbolt and USB 3.0 ports for those who want to be sort of "future-proofed" for a few years. Oh some have FireWire and eSATA, too.
  • Come on

    You already own a Mac so it's the norm to be charged double for the same get over it!
    • Come on yourself

      Yeah really?

      I can and do buy hardware at the same price as for PCs.

      This is about Thunderbolt - something that doesn't exist on PCs.

      I remember this whole argument in the days of Macs using SCSI drives. SCSI drives were outside the experience of PC people so they made these statements out of ignorance.

      I now find it funny that I know PC people using SCSI for high end servers and thinking they have found something new and special.

      Adn for the ultimate irony - Go and buy an HDMI cable from any store then compare it to the price that Apple charges for an HDMI cable.

      The going price for HDMI cables at discount electrical chains is $69. Apple charges $20 for their own cable.
      • Fry's

        has lots of HDMI cables for less than $10
  • Apple ThunderBolt cable versus external Mini-SAS cables

    These SFF-8088 locking connectors and the interconnecting cables are only good for 3GB/sec and have no circuitry within. If you look at the price of these, (typically 6 foot cables, usually used to connect hardware RAID controller PCIe cards to external arrays, often 8 drive units as each cable, often used in pairs, is good for four channels of eSATA type data), they tend to be even more than the $50 Apple charges for their proprietary smart cable. So Apple's price is quite fair for the performance of the connections passing through them. The only problem is the low end user who expects low prices and gets low performance from single hard drives. USB 3.0 is better suited to these commodity users. The next generation motherboards will support this, and I imagine Apple will embrace it sooner or later, and use USB 3.0 on iPads and iPhones to speed up wired syncing. The real shame is the lack of legacy adapters (TB to FW800 and/or FW400) for the masses with FireWire connected drives.
  • The cable is ok..

    But I would have expected Thunderbolt attached docking stations, like the Apple's Thunderbolt Display (without the display) to appear sooner from various manufacturers.

    Thunderbolt is really an PCI-Express (x4) extension bus. You can have any kind of peripheral on the other end, including USB 2.0, USB 3.0, FireWire, Gigabit Ethernet... The fact that it can also transport Display Port traffic is an added bonus.

    With PCI-Express 3.0 Thunderbolt is going to become even faster..
  • Please use logics, good thinkings with Thunderbolt

    I was surprised by how skin-deep the writer of the article is, in view of his opinion to many aspects of Thunderbolt. Any "good" technical person with reasonably length of exposure in the high-tech industry should know that cost and performance are associated with the shipping volume of the devices in which a new technology is being adopted. Currently, it is obvious that only Apple has been selling computing devices with Thunderbolt while Lenovo / Asus / Sony are next to follow (based on press releases). While several hard drive vendors already release devices with Thunderbolt, monitor vendors are relative scarce with their new product. Two issues are common to every new technology: 1) Thunderbolt was first developed by Intel with heavy involvement from Apple, but Intel has not open up Thunderbolt to whoever interest at developing compatible devices, 2) everything, from cables to testing the systems and the components, is going to remain expensive for a while especially since the technology is relatively new. Unless Intel really opens up (i.e. royalty-free) Thunderbolt to the whole world, devices will remain relatively expensive compared to USB3.

    By the way, USB3 is really not that great despite of being one level higher than USB2. Devices and components are more expensive than USB2 which is really very very cheap. Besides, the bandwidth of USB3 is relatively "restricted" when compared to the copper cable equivalent of Thunderbolt and its future variants. It would be beneficial for Thunderbolt to merge with the external version of PCI-Express 4.0 (probably 16Gbits/s). In fact, there is no reason why this cannot not happen fast especially when Intel and Microsoft are willing to drive the technology. For storage applications, USB3 is so slow and so inefficient (~80% for the net throughput at best, while SATA3 and PCI-E 3.0 are relatively much more efficient!). As the whole world is moving to "green", USB3.0 is so wasteful when compared to PCI-E 3.0 and SATA3.0 and other newer technologies! In principle, a variant of USB3 is somewhat green (signaling is more contemporaray) but no device can implement this (at least in the next 5 years) because of the curse of "backward compatibility". I am glad to see its half-brother, Wireless USB, to go away because the protocol translation and the inefficiency to send data wirelessly are simply pathetic. But then, a lot of technical writers/editors praised upon Wireless USB at the time. Once again, think more and use logics!

    Effectively, USB3.0 gives you little "real world" benefit while it also becomes an obstacles to better technologies. Anyone who follows USB for the past 15 years should admit that USB3 is a patch-up of USB2 which is a patch-up of USB1. Well, how many bandages does it make sense to patch up a technology without breaking the "backward compatibility". Nothing last forever and remains the same. As a technical editor, you should promote the logical approach, eliminate the "hype" (producers of the older technology and devices have more interest to keep selling similar stuff to the consuming publics, rather than to sell the "good" and "right" stuff, or else these producers have to put in new investment, hence the ROI story!).

    Once again, USB3 is somewhat like Wireless USB, the value additional to USB2 is not that great. Imagine, if storage devices move quickly to the much optimized NVMe or SCSI-over-PCIe, the speed would be astonishingly fast and smooth ... Please, think and look around more, and your articles will become more than skin-deep and your readers will be benefited :) To clarify, the PHY of Thunderbolt is different from the PHY of DisplayPort, albeit they are technically all AC-balanced and of LVDS type. By the way, I didn't disclose any confidential information here as these are all public information (just that you have to spend more time to look around!). Thank you for the patience to read my comment, whatever.
  • History

    It took 18 months for USB to take off, and it was largely because of the iMac's introduction that vendors finally started designing peripherals to work with it, since it didn't use legacy ports. They saw an opportunity and went for it. PC vendors came along kicking and screaming until they saw it was a good thing, then they pretended they were responsible for it.

    Go figure.
    • History

      You were correct. Since I started to get involved with USB since CY1994, I can attest to your assertion that the success of USB is attributed to effort by Apple. This was one of the rare occasion that Apple didn't act evily :) With the Thunderbolt, Apple could be contributing to the emergence of another mass-market interface that is both cheap and versatile. The PC guys, in my opinion, are a bunch of soul-less and gutless cheap idiots. They can give us the the Ultrabook at least 5 years ago, but choose to offer the heavy and ugly brick (>6lbs, low resolution, 1.4" thick, etc.) This time though, it seems that they are willing to push the PCI-E 4.0 to outside-the-box sooner. Once realized, we will have one single high-speed cable between the mobile devices (notebook, tablet) and external peripherals - a true universal docking port! Forget about the lowly USB3 which is becoming a joke (look at the new USB3 connector which practically joins two pieces together, so ugly and wide)! Hop on to the next millenium bus!