Sapphire GearBox Thunderbolt 3 Review: Discrete Graphics On The Outside

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Today’s external graphics enclosures are liberating to the legions of gamers who travel around by day but want to buckle down for a frag fest at night. They impose nothing on your choice of laptop, other than it must include Thunderbolt 3 functionality. Go thin. Go light. It doesn’t matter. Then, when you get home, hook right up to USB-C and enjoy supercharged performance that would have necessitated hauling around a larger, heavier notebook.   

Sapphire’s GearBox Thunderbolt 3 enclosure gives mobile gamers the option of working on their productivity-oriented systems all day, and then bolting on the muscle at night. It even goes multiple steps further, exposing gigabit Ethernet and a pair of USB 3.0 ports to platforms that might not have room for those interfaces along their edges. It can charge laptops that use up to 60W. And it’s compatible with AMD or Nvidia graphics cards rated for 300W or less. For all intents and purposes, the GearBox is a utilitarian piece of hardware that utilizes a useful technology to do some things that wouldn’t have been possible a few years ago.

But there’s that little issue of frame rates. We think it’s pretty reasonable to buy an add-in graphics card and expect benchmark numbers from it commensurate with the reviews you read online. You shouldn’t have to spend Radeon RX 590 money to get Radeon RX 570 frame rates. Sapphire’s engineers say a ~20% performance hit is to be expected, and in some games, we saw less slow-down. But in others, we saw more. Some of this may be attributable to the Intel Thunderbolt controller attached to our test system’s Platform Controller Hub versus running the same GPU in a CPU-attached PCIe slot. Or maybe it’s the 4C/8T desktop Core i7 we used for benchmarking. A lower-power mobile chip would have likely masked the performance delta by bottlenecking both graphics configurations. Either way, the potential delta is painfully apparent under the right conditions, and you shouldn't have to count on it being diminished by an artificial bottleneck.

Now, you may have noticed that we snuck a few results into our benchmark charts from Intel’s HD Graphics 630 engine. In Tom Clancy’s Ghost Recon Wildlands, it doesn’t even average 7 FPS. The performance under Grand Theft Auto V is even worse. We know there are ways to coax better frame rates from integrated graphics. But we’re not interested in compromising quality for a barely-playable experience. We want compelling gaming from that svelte little Ultrabook. Is that too much to ask?

If you have to choose between gaming on integrated graphics or a hobbled add-in card via Thunderbolt 3, the GearBox looks like an all-star. Just be aware that the reality of its implementation means you’re going to leave a lot of rendering horsepower on the table in exchange for a convenient external connection. And at $259, you’re paying a premium on top of the cost of your add-in board. The alternatives don’t look much better, though. Enthusiasts willing to accept the frame rate hit can expect their best value from an external graphics enclosure like Sapphire’s GearBox.

Image Credits: Sapphire

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Chris Angelini
Chris Angelini is an Editor Emeritus at Tom's Hardware US. He edits hardware reviews and covers high-profile CPU and GPU launches.
  • LordConrad
    "Discrete graphics, gigabit Ethernet, and USB 3.0 from one enclosure"

    This is not a Pro, because all devices connected to the enclosure will share the bandwidth of that single Thunderbolt 3 connection. Any use of the Ethernet and/or USB ports will steal bandwidth from your graphics card, which is already bandwidth starved from being on Thunderbolt.
  • abhipw
    How can an always on blue light bar be a con?
  • cangelini
    abhipw said:
    How can an always on blue light bar be a con?
    If it's on your desk, and you're always looking at it, an always-on light becomes a con. When it comes time to watch a movie or play a game, you'll want the ability to disable it.
  • mlee 2500
    Call me old fashioned, but I put my GPU directly inside my computer.