With a dozen Thunderbolt 3 eGPU enclosures currently available on the market, we now have more options that either maximize performance or portability. The latest entry is the Breakaway Puck from Sonnet Tech. Built to be the most portable external graphics solution (eGFX), it’s neither particularly powerful nor cost-conscious. The Sonnet Breakaway Puck is intended for multi-monitor expansion or as a compact setup for eSports gaming. Sonnet is catering to a niche group of customers in a very niche market, and I commend its commitment. So for those whose needs are perfectly met by a handheld eGPU, it’s the best thing since sliced bread.
Recent studies show American youth is losing their grip strength. Tech companies share some of the blame with their continuous advancements in the workplace and through thinner and lighter electronics. The Sonnet Breakaway Puck is a very clear example of this trend. It took the bulk and mass of a typical eGPU enclosure by relocating the power supply externally. Instead of building an enclosure large enough to house a PCIe graphics card, the Breakaway Puck uses an MXM GPU. Compared to the Breakaway Box that weighs more than 7 lbs, this Puck weighs in under 5.25 lbs including the AC adapter. You need both hands to handle the Breakaway Box. That’s not the case with the Puck.
The four rubber feet at the bottom of the enclosure serve as covers for Philips screws. Opening this bottom cover to access the internal components will void your warranty. The metal housing is very sturdy. Its top cover features a Sonnet Tech logo which glows blue when active. This is also a point of air intake through mesh windows. The single fan disperses heat from the heatsink through cutouts on the sides. Sandwiched in between the heatsink and main Thunderbolt board is the MXM graphics card.
Using an AC adapter to power an external graphics card is a concept most eGPU enthusiasts are familiar with. Prior to the all-in-one enclosure with an internal PSU design, we have been building eGPU boxes out of the AKiTiO Thunder2 and Thunder3. The PSU of choice was often a Dell DA-2 220W. Sonnet enhanced this concept in the Breakaway Puck. It uses a Mean Well 160W power brick for the RX 560 media sample I received. This PSU is both lighter and smaller than the Dell DA-2.
The cooling fan is a 75mm unit made by Apistek. It’s whisper quiet most of the time. The only occasion I noticed it running full speed was during initiation with the host computer to activate AMD XConnect. This process only lasts a few seconds. I can’t speak for the RX 570 version, but in the Sonnet Breakaway Puck RX 560 this cooling fan is sufficient. With the power supply not located inside the enclosure, this eGPU runs relatively cool.
The Sonnet Breakaway Puck contains a Thunderbolt 3 main board that’s arranged to uniquely work with an MXM card. The main differences with the other eGPU enclosure boards are a slot for the MXM card and the video output ports. Next to the Thunderbolt 3 port are an assortment of one HDMI and three DisplayPorts. The crucial controllers and IC for a Thunderbolt 3 external graphics card are all here: Texas Instrument TP865983 USB-C controller, Intel DSL6540 Thunderbolt 3 controller, and Winbond EEPROM.
Testings & Benchmarks
I’m not the target audience for this enclosure, but my wife immediately saw the appeal of this Sonnet Breakaway Puck, asking why all the other enclosures I reviewed were so large. The Puck has the same appeal as a Mac mini – a very small footprint, compact enough for you to pick it up just to admire the form factor. It just made sense to pair this Breakaway Puck RX 560 with a Mac mini for testing in macOS.
The RX 570 version (shares same PCI ID 67DF with RX 580) is plug-and-play with macOS 10.13 native eGPU support. The RX 560 however does not have this same fate. It’s not hard to enable eGPU for it though. Goalque created and packaged automate-eGPU.kext installer for 10.13 to make this process easy. Once I ran this installer, the Sonnet Breakaway RX 560 works great with a 2011 Mac mini via the Apple USB-C/Thunderbolt 3 to Thunderbolt adapter (Thunderbolt 1 speed). The process is the same as with the natively supported RX 570/580; I hot plug the eGPU, macOS notifies me to log out to enable external GPU then log back in to use.
Power delivery is only possible when paired with a Thunderbolt 3 host computer. I tested with a late 2016 15″ MacBook Pro and saw 45W PD through this Breakaway Puck. Thunderbolt firmware version is 25.1 which should not have the H2D bandwidth issue found in earlier eGPU enclosures.
If you recall back in March this year, I ventured into building a custom AKiTiO Thunder2 RX 470 eGPU and mounted it on the back of a monitor. That idea was very well-received. Sonnet made that a reality in this Puck. It offers a Puckcuff VESA mounting kit ($59) for you to accomplish this same task. For more pictures of the Breakaway Puck and Puckcuff, please read my unboxing post.
For performance testing, an ultrabook would make the best pairing for the intended use of this product. The release of this enclosure coincides with Intel 8th generation quad-core ULV CPU availability. I used a late 2017 Lenovo Yoga 920 for this review. This ultrabook has the i7-8550U that many eGPU enthusiasts anticipate will boost external graphics performance.
I sound like a broken record, but it bears repeating there are two main performance hindrances on ultrabooks paired with eGPU. The first one is PCI Express lane assignment for Thunderbolt 3 connection. The ideal arrangement is 4 data-transmission PCI Express lanes but many come with only 2 lanes. The second issue is whether the laptop is set for low-power GT2 OPI mode or high-performance GT4 OPI mode. This information is unfortunately not available on the spec sheet from the manufacturers. We want to bring more awareness so that eventually the PC OEMs will provide this detail for future products. The good news is this Yoga 920 has both x4 PCIe connection over its Thunderbolt ports and runs in GT4 OPI mode. The Sonnet Breakaway Puck provides sufficient power to charge this laptop through the Thunderbolt 3 cable.
I didn’t have any eSports games to test. Sonnet provided these tests they did in-house. I ran my usual set of synthetic benchmarks, except I changed the settings to Medium at FHD. These were run through the Intel UHD Graphics 620 iGPU with the internal display and Sonnet Breakaway Puck RX 560 eGPU with an external monitor. Here are the numbers:
|Lenovo Yoga 920||Intel HD 620 iGPU||AMD RX 560 eGPU|
|3DMark Time Spy||582||2,163|
|3DMark Fire Strike||1,123||4,807|
|Tomb Raider 2013||18.0 FPS||70.8 FPS|
|Shadow of Mordor||14.5 FPS||49.0 FPS|
|Dirt Rally||15.5 FPS||48.8 FPS|
|Hitman||18.0 FPS||63.8 FPS|
With electronics, smaller and lighter often comes with a hefty price. The Sonnet Breakaway Puck is no exception. It accomplishes the mission of being the most compact external graphics solution on the market. At $449 for the RX 560 and $599 for the RX 570 version, the Breakaway Puck is a compromise on performance given the alternatives. Nevertheless it still roughly quadruples the performance of an Intel iGPU. If portability is the main priority, net yourself a Breakaway Puck.