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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  • Dug - Thursday, January 12, 2012 - link

    We haven't even seen a good hub yet, or even a simple drop in hard drive enclosure.
    I wish manufacturers would jump on this because there is demand out there.
  • mckirkus - Thursday, January 12, 2012 - link

    The problem is cost. You can get a USB3 external enclosure for $14 that will handle bandwidth from all but the most expensive SSDs.

    USB3 = 5Gb/s
    SATA3 = 6Gb/s
    TBolt = 10Gb/s
  • iwod - Thursday, January 12, 2012 - link

    You didn't factor in USB 3 has the worst bandwidth efficiency in your Three Listed IO Port.
  • madmilk - Friday, January 13, 2012 - link

    Well, the average consumer is using a hard drive (not SSD, not a RAID array), which will run perfectly well on USB 3.0, despite its inefficiencies.

    Sure, there will be T-Bolt RAID arrays (and those already exist with eSATA, through port expanders). But be prepared to spend plenty of $$$ for your niche component.
  • barefeats - Sunday, January 15, 2012 - link

    I have tested a fast 6Gb/s SATA to 5GB/s USB3 bridgeboard (Koutech ASU330) with the fastest USB3 host adapter (RocketU) and fastest 6Gb/s SSDs (OCZ Vertex3 Max IOPS, OWC Mercury Extreme Pro, etc.). The average large sequential transfer speed was 275MB/s.

    I put the same SSDs in a Thunderbolt enclosure (Pegasus X4). The single SSD transfer speed was 466MB/s.

    Then with a fast 6Gb/s SATA host adapter (RocketRAID 2744) in a 6Gb/s rated SATA enclosure, I got 510MB/s.

    A pair of 6Gb/s SSDs in a stripe (RAID 0), USB3 = 504MB/s, Thunderbolt = 767MB/s, and 6Gb/s SATA = 1003MB/s.

    Four 6Gb/s SSD in RAID 0, USB3 = 954MB/s, Thunderbolt = 855MB/s, and 6Gb/s SATA = 1864MB/s.

    Not quite a fair fight in the two and four SSD RAID sets. The USB 3.0 and SATA setups had a dedicated data channel for each drive. Thunderbolt had one data channel shared by all drives.
  • zanon - Thursday, January 12, 2012 - link

    Didn't Nvidia add a bandwidth compression system in the 258 drivers (and later) for a certain small subset of systems (Intel IGP, Optimus, x1 link)? I've seen a lot of benches from people (and in the GUS II thread someone linked a big list of DIY eGPU examples) that seem to indicate surprisingly good performance, even with higher end cards. Particularly if Nviida enabled their compression (TB more like an x2.5) it certainly looks as if, short of something SLI/multiscreen, performance could be pretty solid even with mid-range (560/6870-class say) cards (and naturally it would slaughter anything integrated). Having future CPUs that can also scale up their TDP while on mains/in a cooling dock would make it even better.

    I do hope Intel changes their mind here, as long as they're maintaining backwards compatibility it'd preferable to see at least one speed bump as soon as feasible. Doubling the bandwidth would do a great deal to make this a non-issue. Even if they don't though it's still exciting.
  • dcollins - Thursday, January 12, 2012 - link

    Thunderbolt is a great technology. The idea of having a laptop/tablet to carry around, then being able to plug in a single cable at my desk and have a high speed gaming computer is quite appealing.

    In my mind the biggest concern is that all controllers are coming from Intel. Until other manufacturers can produce competing TB controller, pricing will remain high, which will prevent widespread adoption.
  • damianrobertjones - Thursday, January 12, 2012 - link

    eGPU/ViDock... done
  • TrackSmart - Friday, January 13, 2012 - link

    Sony already has an implementation of this on their Vaio Z. They used a pretty mediocre GPU, which may have been due to the bandwidth limitations of this early thunderbolt interface:

    From CNET:
    We tested the system's gaming chops both with the external GPU and without. Running only on the internal Intel HD 3000 graphics, Street Fighter IV ran at 11.7 frames per second (fps), at the native 1,920-by-1,080-pixel resolution. Connect the docking station and its AMD 6630M GPU, and we got 29fps on the same test. In the much more challenging game Metro 2033, we got 12.1fps with the external GPU, which is actually a pretty good score, considering we ran the game at 1,920-by-1,080 pixels in DirectX 11 mode with graphics set to high.

    We'll probably need the full-speed version of Thunderbolt to have any chance at even mid-range gaming capabilities from an external GPU...
  • cz - Thursday, January 12, 2012 - link

    This option paves the road for an ultra light notebook with full featured docking station combo or even tablet with docking station.

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