Till now, you’ve had two choices to increase the port capabilities of your laptop computer: a cheap USB-C dongle or a extra highly effective, expensive Thunderbolt dock. A 3rd choice is quietly rising, attempting to separate the distinction. A DisplayLink dock (generally referred to as a USB-C dock) makes use of knowledge compression to supply the capabilities of a Thunderbolt dock over a regular USB-C cable.
USB-C hubs, Thunderbolt docks, and now DisplayLink docks have emerged due to two elements: the rising ubiquity of do-anything USB-C ports, and the conclusion by laptop computer makers that they will use these ports to eradicate all of the devoted HDMI, microUSB, SD card slots, and USB-A ports that may litter up their pocket book PCs.
Conventional USB-C hubs and Thunderbolt docks differ in each worth, measurement, and accessible bandwidth. The latter issue has historically been the differentiator between the 2 merchandise. A 10Gbits/s USB-C port merely doesn’t supply as a lot bandwidth as a 40Gbits/s Thunderbolt port, and the extra bandwidth might be dedicated to extra shows, ports, and so forth.
However the knowledge compression provided by DisplayLink over the USB-C port places lesser-equipped laptops on a extra equal footing. Principally, they let you add many capabilities of a contemporary Thunderbolt-equipped laptop computer even for those who personal an older laptop computer with out Thunderbolt ports.
DisplayLink USB-C docks: execs and cons
DisplayLink docks subsequently present a few of the native capabilities of a Thunderbolt dock, particularly the power to drive a number of high-resolution shows. Due to the inherent bandwidth limitations, they’re a sensible choice for workplace employees, who can use these further shows for static functions like e-mail, chat, spreadsheets, or workplace work.
They do, nevertheless, have some elementary limitations. For one, DisplayLink docks aren’t designed for gaming or driving exterior GPUs. USB-C docks and Thunderbolt docks alike are additionally typically plug-and-play proper out of the field. A DisplayLink dock requires software program drivers to allow knowledge compression, so that you’ll must obtain the suitable DisplayLink software program from the dock producer. Sadly, how DisplayLink interacts together with your PC and GPU implies that your Home windows PC will generally encounter glitches, akin to the lack for gadgets like KVM switches and powerline adapters to work correctly.
The most effective USB-C hubs and dongles sometimes price between $25 and $40. Whereas a journey Thunderbolt dock can price about $170, the very best Thunderbolt docks often price between $250 to $300 or so. That’s additionally the value vary of latest DisplayLink docks just like the Plugable UD-ULTC4K, although, which retails for $279. We haven’t examined any low-cost USB-C hubs that provide DisplayLink compression inside, although we’ll level you to some later on this story.
Looking for a DisplayLink dock is usually a bit complicated, too, because the time period “DisplayLink dock” isn’t actually in vogue. As an alternative, distributors will generally use “USB-C dock” as an alternative. We sometimes think about a USB-C hub as a part of the exploding variety of dongles related by a USB-C cable to the host PC. These dongles sometimes embrace just a few USB-A ports, a USB-C port for charging or additional enlargement, and sometimes an HDMI port or Ethernet port. We think about a USB-C dock to be a bigger gadget, presumably powered, with much more enlargement choices. However these bigger docks might not have the DisplayLink capabilities referred to as out within the specs, and even supply them. You’ll want to buy fastidiously.
DisplayLink dock efficiency, examined
Plugable despatched us considered one of their UD-ULTC4K USB-C docks for overview. Technically, it’s a refresh of the corporate’s current USB-C Triple 4K Show Docking Station (which has since been up to date on Amazon’s web page), particularly providing the selection of both DisplayPort 1.2 or HDMI 2.0 ports for every show — an expensive choice. It ships with a regular 10Gbps USB-C cable and a 135W energy adapter that may provide as much as 95W to the host PC or 19.8W to a telephone by way of the front-mounted USB-C port. On the entrance of the UD-ULTC4K you’ll additionally discover an SD card and mic and headphone jacks. On the rear, Plugable consists of 4 5Gbps USB-A ports, the USB-C connection to the host PC, the facility cable, and an Ethernet jack.
Mark Hachman / IDG
It’s the three HDMI/DisplayPort connections which can be value being attentive to. (DisplayPort, one of many show requirements used to connect with a show, has nothing to do with DisplayLink, by the way.) Two of the three units of HDMI/DP ports on the UD-ULTC4K use DisplayLink compression, and are indicated as such. The third takes benefit of a laptop computer characteristic referred to as DisplayPort Alt Mode to offer a greater, direct connection between your laptop computer and the show itself. (Sadly, the business has performed a completely horrendous job explaining which USB-C-equipped laptops help DP Alt Mode and which don’t; chances are high, nevertheless, yours does.)
So why does this matter? As a result of right here, the DP Alt Mode port is the “good port,” and can connect with an exterior 4K show at 60Hz, which is extra snug in your eyes. I related a second 4K show over the DisplayLink port (utilizing HDMI) and will solely join at 30Hz — high quality for a secondary monitor, however the slower refresh fee can fatigue your eyes. Sadly I didn’t have a 3rd 4K show available, and related the dock to a 1080p (at 60Hz) show as an alternative by way of the DisplayLink/HDMI port. That labored simply high quality.
The problem, because it at all times is, is out there bandwidth. Whereas Thunderbolt supplies 40Gbits/s of bandwidth, DisplayLink should finesse itself by way of 10Gbits/s. In sure instances, that issues; in others, it completely doesn’t.
PCWorld checks dongles, docks and hubs partially utilizing a 4K, 60Hz take a look at video streamed from YouTube. However YouTube doesn’t at all times ship what you request, primarily based on its data of your {hardware} and the way properly it performs again video. YouTube solely performed again the “4K” video at 1440p, upscaled to near-4K high quality. Then again, it solely dropped 35 frames out of 10,000. In real-world phrases, YouTube delivered good high quality video with hardly any stutter.
That modified once I tried copying a big set of recordsdata from an exterior exhausting drive over the identical bus. Abruptly, YouTube dropped frames like loopy — 1,223 out of 10,000 — and needed to pause the video whereas it caught up. The video high quality defaulted to 1440p within the settings menu, and delivered lower than that. There was some noticeable stuttering — nothing too dramatic, however there. Protected content material performed again by way of Netflix, nevertheless.
We have been explicitly instructed to not recreation on the UD-ULTC4K, however tried it out anyway. We found what you would possibly anticipate: largely staticly rendered video games like Cities: Skylines performed with completely no noticeable drop in body fee in any respect, even at 4K. Whole Battle: Shogun 2 performed equally. We didn’t take a look at the newest first-person shooter on our price range pocket book, however in any other case the UD-ULTC4K carried out significantly better than anticipated.
You might even see some critiques of DisplayLink USB-C docks that point out that DisplayLink doesn’t play good with discrete GPUs. That could be the case, however utilizing two laptops — one with a discrete GPU (a Microsoft Floor Laptop computer Studio), and one with built-in graphics (a Microsoft Floor Laptop computer Go 2) — we noticed no distinction in efficiency. Nor did we see any change in utilizing the included, commonplace USB-C cable versus swapping it for a devoted Thunderbolt cable, both.
Must you purchase a DisplayLink USB-C dock?
Not all DisplayLink docks are created equal. One of many troubling points with extra superior DisplayLink docks just like the Plugable UD-ULTC4K is that it provides a really tough equal to a Thunderbolt dock, but for the value of a full-fledged dock itself. What we’d hope for, nevertheless, is a worth that’s someplace in between that of a generic USB-C dongle and a full-fledged Thunderbolt dock.
Whereas we haven’t examined both the $89 GIQ USB-C Hub or the $89 IVIIN USB-C Hub, each of those DisplayLink hubs hit that candy spot, price-wise. However the specs fall a bit quick: the GIQ dock helps as much as two 2048×1152 shows, whereas the IVIIN claims that one show will help 4K60, whereas the opposite will help 2048×1152. That helps justify the value of Plugable’s dock.
So what to do? When you’re an fanatic who enjoys poring by way of specs and accepting the likelihood that one thing won’t work, DisplayLink does supply an opportunity to increase your PC’s I/O capabilities, even with {hardware} that doesn’t help Thunderbolt. When you aren’t, be happy to return to the relative security of a both a generic USB-C dongle or a robust Thunderbolt dock: each supply simplicity and a identified expertise.
