Connection guides

Dell XPS with two monitors on one USB-C cable: dock, MST chain or Thunderbolt monitor

Two monitors from one cable on an XPS 13 9340, XPS 14 9440 or XPS 16 9640: a WD22TB4 dock, an MST daisy chain such as the U2723QE, or a Thunderbolt chain.

NYBreaking Tech editorial · Accountable publisher: Feroz Sheikh
Editorial update: 2 November 2026 · 5 min read

THE SHORT ANSWER

Dell’s external display guides for the XPS 13 9340, XPS 14 9440 and XPS 16 9640 list up to three 4K 60Hz external displays with the laptop screen on and four with it off, so two monitors on one cable is within the limit. Dell names a Thunderbolt or USB-C dock and daisy chaining as the ways to connect several screens. The Dell-listed dock is the WD22TB4, which supports two 4K 60Hz screens on several port pairs. Without a dock, Windows can extend across an MST daisy chain, for example a U2723QE on USB-C feeding a second monitor from its DisplayPort-out. Dell rates that chain for two 4K 60Hz screens only at an HBR3 link rate.

Manufacturer documentation · Not physically tested by NYBreaking

What Dell documents for each XPS

Model	External 4K 60Hz screens, laptop screen on	Laptop screen off	Port note
XPS 13 9340	3	4	Dell: dock on the left Thunderbolt 4 port
XPS 14 9440	3	4	Dell: dock on the left Thunderbolt 4 port
XPS 16 9640	3	4	Left ports have priority; the right-side USB-C port is not Thunderbolt 4

For 8K, Dell lists a single external display on each model. Dell also says the dock or adapter can limit the number of screens, so the dock’s own table matters as much as the laptop’s. Newer XPS models, including Snapdragon versions, have their own external display guides; check the one for your exact model. Our Dell XPS docking guide compares the docks for these three models.

Three one-cable options compared

Option	How the two screens connect	Main condition
Thunderbolt dock (Dell WD22TB4)	Two dock outputs, for example both DisplayPort 1.4 ports	HDMI and the MFDP USB-C port on the back share one output
USB-C hub monitor with DisplayPort-out (for example Dell U2723QE)	Laptop to monitor 1 by USB-C; monitor 1 DP-out to monitor 2 (MST)	MST on; HBR3 link rate for two 4K 60Hz screens
Thunderbolt monitor with a Thunderbolt downstream port	Laptop to monitor 1 by Thunderbolt; monitor 1 to monitor 2	Active Thunderbolt cable; check the monitor guide for downstream video

All three use the laptop’s native graphics. A DisplayLink dock is a fourth route, but it is not needed on these models for two screens; see DisplayLink vs Thunderbolt for the trade-offs.

Option 1: the WD22TB4 dock

Connect both monitors to the dock first, then plug the dock’s cable into the laptop. Dell recommends that order for docks and adapters.
Use the left Thunderbolt 4 port. On the XPS 16 9640, Dell says the right-side USB-C port does not support Thunderbolt 4.
Pick a supported pair. Dell lists two 4K 60Hz displays on DisplayPort 1.4 + DisplayPort 1.4, DisplayPort 1.4 + HDMI 2.0 or MFDP USB-C, HDMI or MFDP + a Thunderbolt USB-C port, or two Thunderbolt USB-C ports.
Do not use HDMI and the MFDP USB-C port together. Dell says they are muxed and only one works at a time.

The WD22TB4 is also listed by Dell as a supported accessory for all three XPS models. Port roles and limits are in our WD22TB4 profile.

Option 2: an MST daisy chain from a USB-C monitor

Windows supports extended mode across MST chains. Dell’s daisy-chain guide lists DisplayPort, USB-C and Thunderbolt chains as extended or duplicate on Windows, while macOS mirrors MST chains (see daisy-chaining monitors on a Mac).

Connect the laptop’s Thunderbolt 4 port to the video USB-C upstream port on the first monitor, using the USB-C cable that came with it. A U2723QE also charges the laptop over this cable at up to 90W.
Remove the rubber plug from the first monitor’s DisplayPort-out port and connect it to DisplayPort-in on the second monitor.
Check that MST is on in the first monitor’s on-screen menu. Dell says MST is off by default on its monitors; the U2723QE guide adds that the monitor switches MST on automatically once, after a reset, when both cables are connected.
On the U2723QE, open Display Info in the menu and check the link rate. Dell lists two external 4K 60Hz monitors at HBR3 but only one at HBR2, and full 4K 60Hz on both needs Display Stream Compression (DSC) support in the graphics.
In Windows, open Settings > System > Display and choose Extend these displays.

Monitor details are in our U2723QE profile.

Option 3: a Thunderbolt monitor chain

Dell’s daisy-chain guide says a Thunderbolt chain needs a first monitor with a Thunderbolt-out port and an active Thunderbolt cable, and that each monitor needs its own power. Dell lists Thunderbolt 4 UltraSharp models such as the U2724DE and U2725QE; confirm in your model’s user guide which downstream port carries video. Intel says Thunderbolt 4 can drive up to two 4K 60Hz displays or one 8K 60Hz display on one connection. Dell notes that resolution, colour depth, DSC and the monitor’s data-versus-video priority setting can all affect what the chain delivers.

If the second screen stays dark

The second monitor is not detected: follow second monitor not detected in Windows 11 through a dock. In an MST chain, check the MST setting and the link rate first.
A screen blanks for a few seconds and returns: see monitor goes black for seconds through a dock, which covers DSC and dock firmware.
4K stuck at 30Hz: see 4K monitor stuck at 30Hz through a dock.
The laptop does not charge: see USB-C monitor not charging the laptop or dock not charging the laptop.

Sources you can inspect

Based on official documentation reviewed 2026-11-02. Steps are general; follow the manual for your exact model. No physical test by NYBreaking.

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