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OWC Mercury Helios FX 650 Thunderbolt 3 External GPU Enclosure
Computer Reviews

OWC Mercury Helios FX 650 Thunderbolt 3 External GPU Enclosure

OWC aims for the mainstream with their Thunderbolt-based external graphics box for laptop PC gaming.

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A couple years ago, Thunderbolt (Gen 3) brought the idea of mainstream innovation to the computing enthusiast universe, in the form of external graphic boxes (eGPU). Initial reception for PC platforms was lukewarm with various reasons for its failure to launch; possibly due to timing and the apparent lack of affordable laptops equipped with the interface that weren’t MacOS. You had to pony up a couple grand just to gain the privilege, and this was before investing another pile of Benjamins on a separate enclosure and graphic card.

Fortunately, the market is catching up as affordable laptops become available that are not MacOS-based. Knowing this, it’s probably a good a time as any to take another look at the Mercury Helios FX 650 from Other World Computing, Inc. A plug-and-play expansion GPU intended for desktop-like performance, whether it’s better graphics or productivity demands beyond what most laptops can provide.

The enclosure is meant to hold a single card and nothing more, so stylishness takes a backseat to being a basic steel case with a removable cover that features ventilated panels on the sides. Open it up and the simple layout continues with an 650W High Power HP1-J650GD-F12S power supply (hence the name) with a 24-pin ATX, 120mm fan, and a single PCIe slot making up the inside. For connectivity, a single 1.5 ft (0.4m) Thunderbolt 3 cable is also included.

If this review is starting to sound familiar then you aren’t wrong, I covered something similar from Sonnet called the Breakaway Box and it promised the same advantages. I recall liking it, but it was kind of pricey at the time and equally no frills—Hell, the OWC Mercury Helios FX and Sonnet Breakaway Box also sport the exact same appearance. No joke, the chassis design is sourced from the same unknown supplier, which made the unboxing seem like déjà vu.

That is the biggest elephant in the room if you happen to be cross-shopping these specific models, but it helps to know that OWC offers 550W or latest 650W configurations with an optional Gigabyte Radeon RX 580 bundle from approved vendors (MacSales). The Mercury Helios FX will also be the slightly cheaper option, especially if you’re adamant on pairing you own midrange AMD or Nvidia card (BYOGPU) instead of bundling it.

Setup of the Helios FX is straightforward. You’ll need a graphics card and a direct link to the host computer via a Thunderbolt port for full bandwidth (and maybe a couple of reboots), otherwise it won’t power on at all through daisy-chaining. You probably knew that already, but you do get some benefits as it can charge laptops of up to 100W of power. This will be enough juice to breathe life into Macbooks and some laptops in just a couple hours. It also runs whisper quiet with the fan whirling at 10dB no matter the card nestled inside. Supplemental connections such as Ethernet Gigabit/1000Base-T and USB are omitted for stability purposes but as I said earlier: “no frills.”

Because there are many variables on how effective the Mercury Helios FX is performance-wise, it helps to understand what cards actually stand to benefit and/or retain benchmarks by running in a separate enclosure. Theoretically, you could pair it with something magnificent like a NVIDIA TItan V, Radeon VEGA FE, or even a coveted NVIDIA TITAN RTX for intense engineering or deep learning machine on a lightweight laptop. Keep in mind that all Thunderbolt devices have a bandwidth ceiling of 40Gbps (~5,000MB/s) versus 126.08Gbps~15,760MB/s on 16X PCIe 3.0 equipped motherboards, and subjected to bus throttling as an external device. It’s an unavoidable factor for any eGPU utilizing the interface, and lofty difference compared to hardcore gaming desktops fitted with similar flagship cards.

If you’re aware and comfortable with it, then the Mercury Helios FX is still more than suitable; ideally for graphic design, video editing and moderate PC gaming in that order. I Paired the Helios FX with my GeForce RTX 2080 Ti, and the guinea pig laptop being a Lenovo YOGA 720-15IKB equipped with an Intel Core i7-7700HQ CPU, 16GB DDR4 SDRAM—this also has its own discrete GeForce GTX 1050 by default for mobile entertainment. This allowed me to not only test the possibilities of the box itself, but also see if there were any distinct advantages over a discrete mobile GPU versus one hooked up via Thunderbolt 3.

My primary goal was to achieve performance-oriented gaming by any reasonable means; playing games like Resident Evil 2 (2019), Forza Horizon 4, and Crackdown 3. I began with initial auto-detected maximum presets and gradually worked downward, with all titles failing to reach a 4K/60fps target. Perhaps I was hoping for too much, but things do improve somewhat at 1440p with a targeted 30-44fps/ultra and a broad 44-59fps at medium-high settings (Vsync Off). I experienced overall losses of 17% from a Radeon RX 580 (better), 28% for a RTX 2070 (balanced), and up to an astonishing 41% deficit on my RTX 2080 Ti which put it on the level of an OEM RTX 2070.

This brings up the argument of a discreet GPU on laptop versus daisy-chain linking. In its defense, the Helios FX can be upgraded indefinitely and did provide sizable gains in overall graphic quality and resolution, but still fell short in targeted frame rates—or no discernible advantage at all in cases like RE2 and Shadow of the Tomb Raider on high presets. It’s obvious that Thunderbolt has potential if left on medium/high settings, mostly, but its current specifications are still impeded for raw gaming. I didn’t have time to directly test since my focus was on Windows machines, but compatible Macbook and iMac models are also lumped in this phenomenon too. A general rule of thumb for these boxes is that “the better the GPU, the bigger the bottleneck”, apparently.

Because it’s only fair, the Helios FX is relatively more impressive when used for work rather than play. You probably should get this case if your priorities involve any creative project involving the Adobe suites from Illustrator CC and Premiere Pro CC—to AutoCAD, Alias or Maya by Autodesk. Running some benchmarks confirmed what I already knew about the Thunderbolt interface in general. While not delivering unfiltered power in huge chunks, its steady bandwidth processes made for very acceptable workflow benchmarks during Cinebench and 3DMark tests, although the horsepower of my RTX 2080 Ti was markedly reduced to midrange PC figures.

After spending a extended amount of time with the Mercury Helios FX 650 a few realities must be addressed. While Thunderbolt has hypothetically opened the doors for achievable PC gaming on notebooks, it’s not exactly flawless since you have to make peace with performance bottlenecks and compatible laptops remain slim until later this year. Ultimately, this GPU box occupies a area that straddles the best of niche desirability and legitimate practicality, especially if you opt for the Helios bundled with a Radeon RX 580 installed. It all works well enough—you just really have to want it in order to appreciate what OWC is offering here.

About the Author: Herman Exum