The catch
Plugable UD-7400PD
The extra screens depend on DisplayLink software. While it is active, protected video can fail across a Mac, and native HDMI modes vary by host.
Side by side
UD-7400PD vs TBT4-UDZ from Plugable: UD-7400PD gives you screens through software, UDZ keeps the host's native video
Quick verdict
Extra outputs come from DisplayLink on the UD-7400PD, but the TBT4-UDZ relies on native video and host-specific MST support. A supported basic Mac that needs additional office screens suits the UD-7400PD, provided DisplayLink is permitted. The TBT4-UDZ is the pick if your exact Windows or Mac host already supports the native setup you want and you would rather avoid display software. Neither dock has downstream TB for a TB-only SSD, and the four video sockets on the UDZ do not mean four independent Mac screens.
Before you buy
Why, and what it costs you
A software rule from the employer can settle things before the fifth screen even matters
UD-7400PD’s extra outputs rely on installing DisplayLink, which a managed work laptop may not permit. TBT4-UDZ uses native display paths, so a supported host can sidestep that software requirement. The host still has to support the screen count, resolution and MST arrangement you ask for. On a Mac, UDZ’s four sockets do not add up to four independent external screens. If your exact computer already handles the native setup, UDZ can be the easier purchase. If it is a basic M1/M2 Mac that needs two office screens, the software-driven route may be necessary, but you need approval first.
Where this comes from
The DisplayLink requirement is set against the native/MST architecture, under employer policy and exact OS limits. No claim is made that every corporate machine allows all native dock functions.
The catch
Plugable TBT4-UDZ
Native host and MST limits apply. A Mac needs the documented output-group arrangement and does not get the Windows four-screen headline.
Plugable UD-7400PD
- Why pick it
- Your supported basic Mac needs more office screens than its native limit allows, and DisplayLink installation has been approved.
- Compatible 140W PD 3.1 host power would help you, and the screens you need fit the documented output matrix.
- The catch
- The extra screens depend on DisplayLink software. While it is active, protected video can fail across a Mac, and native HDMI modes vary by host.
Plugable TBT4-UDZ
- Why pick it
- Your exact host supports the native screen layout you intend, and you want to skip DisplayLink installation and its Mac video limits.
- A built-in SD reader and a choice of HDMI/DP suit your current desk, and 98W of certified host power is enough.
- The catch
- Native host and MST limits apply. A Mac needs the documented output-group arrangement and does not get the Windows four-screen headline.
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What this page compares
UD-7400PD vs TBT4-UDZ for several office screens, basic Macs and a managed work laptop. Get to grips with software permission, display groups and charging.
Each is a desktop dock built around screens, with no downstream TB accessory ports. They reach their headline display counts by different architectures, and that matters more than counting the visible video sockets.
Which one fits
Pick the situations that sound like you
A basic M1/M2 Mac has to drive two external office screens
UD-7400PD offers qualified DisplayLink paths, and software is required.
- Plugable UD-7400PD
- Better fit
- Plugable TBT4-UDZ
- Not suitable
The host supports the native layout, and DisplayLink is not allowed
UDZ does without that display-software requirement.
- Plugable UD-7400PD
- Caution
- Plugable TBT4-UDZ
- Better fit
Regular SD imports should not require a separate reader
UHS-II readers are built into UDZ.
- Plugable UD-7400PD
- Caution
- Plugable TBT4-UDZ
- Better fit
A TB-only drive has to connect via the dock
Neither one offers a downstream TB port.
- Plugable UD-7400PD
- Not suitable
- Plugable TBT4-UDZ
- Not suitable
In practice
Differences you will notice
A software rule from the employer can settle things before the fifth screen even matters
UD-7400PD’s extra outputs rely on installing DisplayLink, which a managed work laptop may not permit. TBT4-UDZ uses native display paths, so a supported host can sidestep that software requirement. The host still has to support the screen count, resolution and MST arrangement you ask for. On a Mac, UDZ’s four sockets do not add up to four independent external screens. If your exact computer already handles the native setup, UDZ can be the easier purchase. If it is a basic M1/M2 Mac that needs two office screens, the software-driven route may be necessary, but you need approval first.
How we worked this out
The DisplayLink requirement is set against the native/MST architecture, under employer policy and exact OS limits. No claim is made that every corporate machine allows all native dock functions.
A basic Mac and a Mac used for movie night may call for different answers
UD-7400PD’s DisplayLink paths can give a basic M1/M2 Mac extra office screens, while UDZ stays limited by the Mac’s native stream count. That same DisplayLink setup can interfere with protected video across the whole Mac after work. Switching playback to UD-7400PD’s native HDMI is not a dependable way around that system-wide restriction. If you have a more capable Mac that already supports the native screens you want, UDZ may suit you better for its simpler evening changeover. If you are keeping the basic Mac, you have to decide whether the extra office screen is worth the supported disconnect or disable routine.
How we worked this out
The basic-Mac native limit and DisplayLink’s Mac-wide protected-content restriction. UDZ’s native architecture sidesteps this specific software restriction, with no guarantee for every streaming service or display mode.
The dock that handles more screens may still need an extra card reader
Picture a home desk that runs office screens during the week and takes SD-camera photos on Sunday. TBT4-UDZ has UHS-II readers built in and UD-7400PD has none. If your camera uses SD, UDZ spares you another reader, cable and occupied USB socket. If it uses CFexpress, or you only transfer from a phone, that advantage does not apply. The storage side needs a separate check on both docks. Neither provides downstream Thunderbolt, so a TB-only editing drive still needs a suitable laptop port or a different dock. More display outputs do not finish the camera workflow on their own.
How we worked this out
Documented card-reader presence and zero downstream TB ports on both docks, applied to SD versus other media and a specific TB-only drive. No import-speed claim is made.
Option A
Plugable, UD-7400PD
Plugable UD-7400PD
Your supported basic Mac needs more office screens than its native limit allows, and DisplayLink installation has been approved.
- Best for
- Your supported basic Mac needs more office screens than its native limit allows, and DisplayLink installation has been approved.
Facts we checked
- Extra display approach: Four DisplayLink outputs plus one native HDMI
- Basic M1/M2 Mac: Extra office screens through supported DisplayLink
- Mac output arrangement: Port-specific native and DisplayLink modes
- Host power: Up to 140W PD 3.1
Option B
Plugable, TBT4-UDZ
Plugable TBT4-UDZ
Your exact host supports the native screen layout you intend, and you want to skip DisplayLink installation and its Mac video limits.
- Best for
- Your exact host supports the native screen layout you intend, and you want to skip DisplayLink installation and its Mac video limits.
Facts we checked
- Extra display approach: Native video and host-specific MST
- Basic M1/M2 Mac: One native external screen
- Mac output arrangement: One output from each display group for supported dual use
- Host power: 100W advertised, 98W certified
Spec by spec
Where they really differ
| Spec | Plugable UD-7400PD | Plugable TBT4-UDZ | In practice |
|---|---|---|---|
| Extra display approach | Four DisplayLink outputs plus one native HDMI | Native video and host-specific MST | The decision can flip depending on software policy and operating system. |
| Basic M1/M2 Mac | Extra office screens through supported DisplayLink | One native external screen | A driver download cannot give the native dock another stream. |
| Mac output arrangement | Port-specific native and DisplayLink modes | One output from each display group for supported dual use | Sockets you can see are not interchangeable, independent streams. |
| Host power | Up to 140W PD 3.1 | 100W advertised, 98W certified | Check which profile the laptop accepts before you leave its charger somewhere else. |
| Storage and cards | No TB downstream or card reader | No TB downstream, UHS-II readers included | UDZ can make SD imports simpler, yet neither dock serves a TB-only drive directly. |
Trade-offs
What each pick costs you
With Plugable UD-7400PD
- It has no built-in card reader or TB accessory port. Budget for compatible video adapters that match the actual outputs and screens.
With Plugable TBT4-UDZ
- There is no downstream TB port. The 100W headline figure is 98W certified, which may not be enough to replace the original charger under demanding work.
Change of plan
When the answer changes
You need extra office screens beyond the host’s native limit
Go with Plugable UD-7400PD. If software is allowed, UD-7400PD can add supported DisplayLink paths.
The screens you plan to use already work natively, and the routine should stay simple
Go with Plugable TBT4-UDZ. UDZ sidesteps DisplayLink-specific setup and playback restrictions.
Decision guide
Before you buy
More visible work is the goal, without needing a software exception or giving up how the computer behaves after office hours.
What this page can’t tell you
- There is no claim that a Mac gets four screens in every case, no DRM workaround and no measured latency or performance result. Both docks need exact display-mode checks.
By the numbers
What the data shows
What we found across the docking stations we compare, plus the checked facts behind each finding.
Show the facts and the math
| Product | Needs it meets | Facts we checked | Sources |
|---|---|---|---|
| Plugable UD-7400PD |
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| Plugable TBT4-UDZ |
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Ready to buy
See today’s price and what owners say
Open either model on Amazon for the current price, customer reviews and delivery options.
Plugable UD-7400PD
Your supported basic Mac needs more office screens than its native limit allows, and DisplayLink installation has been approved.
Compatible 140W PD 3.1 host power would help you, and the screens you need fit the documented output matrix.
See price & reviews on AmazonPlugable TBT4-UDZ
Your exact host supports the native screen layout you intend, and you want to skip DisplayLink installation and its Mac video limits.
A built-in SD reader and a choice of HDMI/DP suit your current desk, and 98W of certified host power is enough.
See price & reviews on AmazonEach link opens in a new tab.
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