Plugable UD-3900H vs UD-3900C - Budget DisplayLink Dock Comparison

Plugable UD-3900H vs UD-3900C: the short version

The Plugable UD-3900H and Plugable UD-3900C are closely related budget DisplayLink docks. They target the same desk: two ordinary office monitors, wired Ethernet, a keyboard, a mouse, a webcam, audio, and laptops that may be USB-A, USB-C, USB4, or Thunderbolt. Neither dock is trying to replace a premium Thunderbolt 4 station like the Plugable TBT4-UDZ or a dual 4K DisplayLink dock like the Plugable UD-6950Z.

The practical winner is the UD-3900C. Its score is slightly higher, 6.6/10 versus 6.4/10, and its port layout is simpler for modern desks because both display outputs are HDMI. It also has a longer included host cable, 0.9m versus 0.6m, and it is the newer model by release date. That does not make the UD-3900H obsolete. The UD-3900H costs less by MSRP, lies flat under a monitor, includes DVI-to-HDMI and DVI-to-VGA adapters for older office displays, and has a single native HDMI mode up to 2560x1440 at 50Hz.

If you want the least fussy answer for two HDMI 1080p monitors, buy the UD-3900C. If you are outfitting a mixed office with older monitors, a flat desk layout, and a tight budget, the UD-3900H is still a reasonable pick.

Quick specs comparison

Display support

These docks are more similar than different on display support. Both use DisplayLink. Both are meant for office work, not gaming, protected streaming, video editing, or color-critical creative work. Both require DisplayLink software for video output. On Windows, Plugable says the driver can install through Windows Update. On macOS, you install DisplayLink Manager and grant Screen Recording permission. ChromeOS support is listed on modern releases for both models.

The UD-3900C is easier to explain: two HDMI outputs, both up to 1920x1080 at 60Hz. If your monitors are common 1080p HDMI displays, the setup is direct. Plug in both HDMI cables and move on to the driver step.

The UD-3900H is more flexible for older offices but less clean on paper. It has one HDMI output and one DVI-D output. Plugable includes DVI-to-HDMI and DVI-to-VGA adapters, so the second output can serve older VGA displays or a second HDMI monitor through the adapter path. Its YAML also records a single-display 2560x1440 at 50Hz mode through a native HDMI monitor. That is useful if one desk has a higher-resolution monitor, but it does not change the core dual-display story. In dual-display mode, this is still a 1080p or 1920x1200-class dock.

Neither dock is a good match for dual 1440p, ultrawide, or dual 4K setups. If that is the desk you are building, skip both and read our DisplayLink vs Thunderbolt docking stations guide before buying.

Ports and desk setup

The USB and network story is almost identical. Each dock has two USB-A 3.0 ports, four USB-A 2.0 ports, a USB-B 3.0 upstream connection on the dock side, Gigabit Ethernet, and separate 3.5mm headphone and microphone jacks. The two USB 3.0 ports are the ones to reserve for webcams, external storage, capture devices, or anything that benefits from more bandwidth. The four USB 2.0 ports are fine for keyboards, mice, headset dongles, label printers, and other low-bandwidth peripherals.

The difference is mostly physical layout and video convenience. The UD-3900C gives you two HDMI outputs in a compact vertical-style design. That is cleaner for a modern two-monitor office where both screens already have HDMI inputs.

The UD-3900H lies horizontally and can tuck under a monitor or sit flat at the front of a desk. That body shape can be nicer on crowded desks, classroom carts, support benches, and shared office setups where you want the dock within reach rather than standing upright. It also has the older DVI/VGA adapter path. That is not exciting, but it matters in real offices where monitors outlive laptops by a decade.

Power delivery and cable differences

This category is a tie, and the tie is not flattering. Neither dock charges the laptop. Both need their own DC-barrel power adapter to run the dock and connected peripherals, while the laptop still needs its normal charger. If the goal is a true one-cable desk where the dock handles displays, peripherals, Ethernet, and laptop power, neither model is the right product.

The Plugable UD-3900PDZ is the obvious same-brand step up in the YAML inventory. It adds USB-C Power Delivery up to 100W, a triple-display layout, six USB-A 5Gbps ports, one USB-C 5Gbps data port, an SD reader, and a 3.5mm combo jack. It also changes the compatibility picture because it requires a USB-C host connection, while the UD-3900H and UD-3900C are friendlier to older USB-A desks.

Cable length does give the UD-3900C a small everyday advantage. Its included host cable is listed at 0.9m. The UD-3900H lists 0.6m. On a cramped laptop stand or a desk where the dock has to sit behind monitors, those extra 30cm help.

Compatibility and DisplayLink caveats

Both docks share the same broad compatibility story. They can serve Windows, macOS, and ChromeOS systems. They can also help base Apple Silicon MacBooks drive extra external displays through DisplayLink, which is one reason these older budget docks still show up in office setups.

The catch is the same on both sides. DisplayLink is not native GPU output. The dock compresses video over USB, which is fine for spreadsheets, email, browser tabs, admin dashboards, and call-center software. It is the wrong tool for motion-sensitive gaming, GPU-heavy creative apps, and protected video playback. Both YAML files call out HDCP protected streaming as a problem. Services such as Netflix, Prime Video, Hulu, iTunes, and Blu-ray may show a black screen on attached displays.

For macOS, the setup is also less automatic than a native Thunderbolt dock. DisplayLink Manager needs Screen Recording permission. If displays stay blank after installation, that permission is usually the first place to check. This is not a flaw unique to one of these docks. It is the price of using DisplayLink to add monitors across laptops that may not support native dual displays.

Value

The UD-3900H has the lower MSRP at $95.99. The UD-3900C lists at $119.95. Both carry Plugable’s 24-month limited warranty, and both benefit from Plugable’s support reputation compared with generic USB display docks.

If you compare only the spec sheet, the UD-3900C is the safer default. It scores slightly higher, has direct dual HDMI output, and avoids the adapter story for most modern monitor pairs. That makes it easier to recommend to someone buying one dock for a home office or a hot desk with two HDMI displays.

The UD-3900H wins on price and certain awkward office realities. A horizontal body is easier to place under a monitor. The included DVI-to-HDMI and DVI-to-VGA adapters can save a desk that still has older display inputs. Its single native HDMI 2560x1440 at 50Hz mode is also the only higher-than-1080p display mode recorded between the two YAML files, although it is not a reason to buy the dock for a dual-monitor 1440p setup.

Verdict: UD-3900C wins, but only narrowly

The Plugable UD-3900C wins this comparison because it is the cleaner version of the same basic idea. Two physical HDMI outputs are easier for modern desks than HDMI plus DVI, the included cable is longer, the release date is newer, and the product score is slightly higher. For a buyer with two 1080p HDMI monitors, it is the one I would pick first.

The UD-3900H is not far behind. Its lower MSRP, horizontal layout, older-monitor adapters, and single native HDMI 1440p 50Hz mode give it a real place in the lineup. It is best treated as an office utility dock for mixed monitor inventories, not as a less capable copy of the UD-3900C.

Choose the Plugable UD-3900C if:

• You have two HDMI 1080p monitors.
• You want the simpler display setup.
• You prefer the newer model with the slightly higher score.
• The longer included host cable matters for your desk.
• You are building a hot desk around USB-A and USB-C laptops but do not need laptop charging.

Choose the Plugable UD-3900H if:

• You want the lower MSRP.
• You prefer a dock that sits flat under a monitor.
• You need the included DVI-to-HDMI or DVI-to-VGA adapters for older displays.
• You may use one native HDMI monitor at 2560x1440 at 50Hz.
• You are outfitting a support bench, classroom cart, or office with mixed old and new monitors.

If laptop charging, triple monitors, or 4K displays are on your must-have list, skip both. Start with the Plugable UD-3900PDZ for charging and triple 1080p-class productivity, or the Plugable UD-6950Z for dual 4K DisplayLink without host charging. For broader context, our docking station buying guide explains when budget DisplayLink docks make sense and when a native USB-C, USB4, or Thunderbolt dock is worth the upgrade.