If you use your laptop with multiple monitors, a dock is a necessity. Plugable's UD-3900 is a basic dock that supports dual full-HD monitors and today's most common ports, for just $95. This device doesn't work with 4K monitors, but unless you're an early adopter, the Plugable UD-3900 is an affordable option that can handle just about everything you have right now.
The UD-3900 is a small monolith that stands on your desk, ready to connect your PC to monitors and peripherals. It's made of black plastic and stands vertically, thanks to a sturdy base screwed into the bottom. Plugable's logo and the DisplayLink symbol adorn both sides of the dock.
The dock stands 7.5 inches tall from base to tip, and while the vertical form saves space on your desk, it removes the option to use the dock horizontally under your monitor or laptop, as many Laptop Mag staffers prefer.
The point of a dock is to provide ports that connect your laptop to multiple monitors and a gaggle of other peripherals. On its back, the UD-3900 features two ports for external monitors -- an HDMI port and a DVI port -- as well as four USB 2.0 ports, an Ethernet jack, a USB Type-B port to connect the dock to a laptop, and the power port. There's more on the front: two USB 3.0 ports, a headphone jack and a microphone jack.
The Plugable UD-3900 comes with a DVI-to-VGA adapter for those who still have an ancient VGA-only monitor. However, if your monitor doesn't have an HDMI port (as is the case with most budget screens), you'll need to purchase an HDMI-to-DVI adapter (usually $5) to hook up dual displays.
I connected the Dell Inspiron 17 5000 to the UD-3900 to test its performance with external monitors. The $499 Inspiron has a Core i3- 5010U processor, 4GB of RAM and a 500GB hard drive -- not a powerful computer, but one the average consumer might buy.
I started the testing by connecting one display via the HDMI port on the dock, which maxed out at a resolution of 2560 x 1440. When I played local 4K video featuring scenes of trains, the ocean and a speeding car, the performance didn't even stutter; 1080p streaming of an episode of Last Week Tonight from YouTube was also buttery smooth.
With two displays attached, the monitors displayed a resolution of 2048 x 1152, and playback was still smooth. I added some text editing to the mix, and there was no lag at all. With the monitors attached and no programs open, the Windows Task Manager showed that the CPU was taxed at 1 percent and that 1.9GB of RAM was in use (this includes all of Windows 10 and background processes).
Plugable notes that its dock doesn't work with laptops running Mac OS X or Linux.
The UD-3900 is a budget dock that holds its own. It managed everything we threw at it without experiencing any lag, even when we paired it with a laptop with mediocre specs. Simply put, the performance was impressive for the price. While we don't love the vertical design, some people will appreciate that it takes up less space on their desk.
Those looking for 4K support will need to spend more. For example, Targus' 4K Universal Docking Station, which supports one 4K monitor, is $160. And if you want a dock with USB Type-C, you'll have to wait. If you're not using ultra-HD monitors or planning to upgrade soon, however, the UD-3900 is all you need.