One of the most interesting use cases for Thunderbolt is as a connection to an external GPU for thin and light notebook users, especially Ultrabook/MacBook Air users that are left with nothing more than integrated graphics. We've had concerns about the latency and bandwidth offered by Thunderbolt for use with an external GPU (1.25GB/s in each direction). Despite the concerns, MSI demonstrated a functional external GPU solution at CES this week (the GUS II).
The GUS II is limited to PCIe cards that don't require additional power beyond what's delivered by the slot itself, which ensures that you won't run into the bandwidth limitations that you'd see with higher end GPUs.
While the idea of paring a notebook with a mainstream external GPU is interesting, what's really exciting is the potential to use a high end GPU (think $300+). To enable higher end external GPU support that makes sense we'll need more bandwidth from Thunderbolt. Intel's focus on Thunderbolt is to drive adoption and it doesn't want to quickly rev the spec before the initial release has a chance to gain popularity. As a result, Intel told me that we won't see any increase in Thunderbolt speeds for the next two years. If the technology ramps well (adoption is still very slow as the number of systems with Thunderbolt support are limited and TB devices are expensive) then the market will be ripe for an updated version in 2014.
Expect to hear about a faster version of Thunderbolt in late 2013 and going into 2014.
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  • XZerg - Thursday, January 12, 2012 - link

    Better yet - you can now buy one external GPU and connect to the system that you are using with just plugging one cable. Think about it:

    Buy light/small systems with integrated GPUs to do standard work. When needs be, bring out the external GPU and voila you have the performance - paying only once for the performance, instead of for each system you have just so that they have the needed performance for those few times.

    Would be great for LAN parties too.
  • MGSsancho - Thursday, January 12, 2012 - link

    Or have a PCIe slot on the back of the display and a thunder bolt like dock similar to the new apple displays.
  • hadphild - Thursday, January 12, 2012 - link

    This maybe crazy talk but Thunderbolt could be the new SATA. 10g on a low latency link could really work well for SSDs.

    With ZFS, Windows Storage Pools and caching becoming more common .Very fast access to SSD storage is very much needed. If you have used a Tablet then you know it all about the instant access of IT and not having to wait for bootups.

    Also I work in the AV industry and Fiber Thunderbolt could become the industry standard over VGA. (DVI does not look good over a 20 (60ft) meter cable.) We really need to cables that can do for 300m+ without costing thousands.

    Intel have the Tech we just need other companies to get it all sorted.
  • MGSsancho - Thursday, January 12, 2012 - link :)

    But as a ZFS user myself, I know exactly what you mean :D
  • cendrizzi - Thursday, January 12, 2012 - link

    That's too bad, I was most excited for this application and didn't realize the limitations.
  • Jaybus - Thursday, January 12, 2012 - link

    The technology is not so limited, just the electronic cable. 10 Gbps is about as fast as we can expect to ever have from an electronic cable, and then only for short cable lengths. The photonic version will fix that issue. It's just that the silicon photonics chips needed to make optical Thunderbolt cheap enough to be viable are not yet ready, but they are coming.
  • XZerg - Thursday, January 12, 2012 - link

    I believe cendrizzi meant the power issue, not the bandwidth.

    anyhow i could see some makers providing external power to the card similar to how we have 4/6/8pin molex being attached to current high end cards.
  • repoman27 - Thursday, January 12, 2012 - link

    Actually, it's just the opposite. At the moment, Thunderbolt host controllers are the limiting factor, not the cable, unless you need one longer than 3m (or 1m, I guess, since that's the longest one currently for sale.)

    The only way you can currently max out a Thunderbolt cable is to daisy chain two Apple Thunderbolt displays and a Pegasus R6 full of SF-2281 based SSD's, and then perform a sequential write test using highly compressible data. This would result in 11.6Gbps of DisplayPort packets and 10Gbps of PCIe packets all heading in the same direction simultaneously and overwhelm the cable's total single-direction bandwidth of 20Gbps. This is an absolute corner case, and yet the performance impact would still be fairly minor.

    Until Intel produces Thunderbolt controllers that can push more data, the electrical signaling will do just fine. In fact, current Thunderbolt ports can already be used with optical cables, but the only benefit for the increased cost would be longer cable lengths.
  • MySchizoBuddy - Thursday, January 12, 2012 - link

    similar to powered USB HUB you can have powered Thunderbolt HUB. Not a big issue i say.
  • CharonPDX - Thursday, January 12, 2012 - link

    I've been thinking of the "one plug can carry video to display and high-speed-data to peripherals", but it just dawned on me the reverse can work, too. Just make a Thunderbolt GPU that sends it signal back through the cable to the host system. Portable graphics horsepower on the go! (It would work with the iMac, for example.)

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