The catch
CalDigit TS4
It has no direct HDMI socket. Converting to HDMI takes the correct compatible adapter, and its ordinary USB-C data sockets do not output video.
Side by side
CalDigit TS4 vs Plugable TBT4-UDZ docks: Thunderbolt gear stays with TS4, HDMI screens connect directly on UDZ
Quick verdict
Downstream Thunderbolt equipment stays connected on the TS4, while HDMI screens plug straight into the TBT4-UDZ. If your desk includes a TB drive or another verified TB peripheral, the TS4 is the one to get. If direct HDMI or DP connections count for more, particularly on a supported Windows multi-screen setup, get the UDZ. Note that the UDZ has no downstream TB port and that its four video sockets do not add up to four native Mac displays. The TS4 has no HDMI socket, so HDMI monitors will need compatible adapters.
Before you buy
Why, and what it costs you
Before upgrading screens, a home recording or photo setup should have its peripherals checked
Sometimes a single TB-only drive or Thunderbolt audio interface is what stops UDZ from taking over a TS4-style desk. UDZ has no downstream Thunderbolt port. TS4 has two, and a second monitor may take one of them. If the other screen runs over DisplayPort, a branch can be left for the peripheral. The specific audio interface still needs manufacturer approval for your laptop, OS and dock arrangement, so a spare socket alone says nothing about audio compatibility or latency. If the device also works over USB, or can stay on a separate laptop port, UDZ becomes more practical. Work out which protocol the hard-to-replace device uses.
Where this comes from
Two downstream TB ports against zero, applied to a TB-only peripheral and one DP screen. Audio-interface compatibility and real-time performance are explicitly unverified. A device with dual protocols, or a separate host connection, can reverse the choice.
The catch
Plugable TBT4-UDZ
There is no downstream Thunderbolt port. Extra fixed monitor sockets do not get around the Mac’s native screen limit.
CalDigit TS4
- Why pick it
- The dock has to hold a Thunderbolt-only drive or another verified TB accessory, in addition to a supported screen plan.
- You want several USB-A accessories to stay plugged in directly, and a DisplayPort screen you already own fits the fixed output.
- The catch
- It has no direct HDMI socket. Converting to HDMI takes the correct compatible adapter, and its ordinary USB-C data sockets do not output video.
Plugable TBT4-UDZ
- Why pick it
- Your current HDMI or DP monitors can plug in directly, and nothing needs a downstream TB connection.
- A verified Windows host depends on the supported MST screen layout, while a Mac has to stick to the documented separate output groups.
- The catch
- There is no downstream Thunderbolt port. Extra fixed monitor sockets do not get around the Mac’s native screen limit.
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What this page compares
TS4 vs TBT4-UDZ for HDMI monitors, a Thunderbolt drive and a shared desk that runs a Mac or Windows. Find the connections that the total port count hides.
These are established Thunderbolt 4 desk docks, each with 98W certified host power and 2.5GbE. They go after the same dual-screen laptop desk but trade off differently between native TB expansion and fixed monitor sockets.
Which one fits
Pick the situations that sound like you
A TB-only drive has to stay plugged into the dock
UDZ has no downstream TB ports, but TS4 does.
- CalDigit TS4
- Better fit
- Plugable TBT4-UDZ
- Not suitable
Two HDMI screens should keep their direct HDMI cables
TS4 needs compatible conversion. Check how UDZ groups outputs.
- CalDigit TS4
- Caution
- Plugable TBT4-UDZ
- Better fit
A verified Windows setup calls for more than two external displays
UDZ supports qualified MST layouts, but the exact host and modes are essential.
- CalDigit TS4
- Caution
- Plugable TBT4-UDZ
- Better fit
The laptop requires 140W over the host cable
Each provides 98W of certified host power.
- CalDigit TS4
- Not suitable
- Plugable TBT4-UDZ
- Not suitable
In practice
Differences you will notice
Before upgrading screens, a home recording or photo setup should have its peripherals checked
Sometimes a single TB-only drive or Thunderbolt audio interface is what stops UDZ from taking over a TS4-style desk. UDZ has no downstream Thunderbolt port. TS4 has two, and a second monitor may take one of them. If the other screen runs over DisplayPort, a branch can be left for the peripheral. The specific audio interface still needs manufacturer approval for your laptop, OS and dock arrangement, so a spare socket alone says nothing about audio compatibility or latency. If the device also works over USB, or can stay on a separate laptop port, UDZ becomes more practical. Work out which protocol the hard-to-replace device uses.
How we worked this out
Two downstream TB ports against zero, applied to a TB-only peripheral and one DP screen. Audio-interface compatibility and real-time performance are explicitly unverified. A device with dual protocols, or a separate host connection, can reverse the choice.
Keeping two HDMI monitors means the adapters have to be counted in the decision
UDZ can drive two HDMI monitors directly, as long as you use the right output groups for your host. TS4 has no HDMI output, so those same screens need compatible conversion from its video-capable connections. When you use TS4’s DisplayPort output, CalDigit specifies an active DP-to-HDMI adapter. A passive cable picked up just because the plugs match is not the documented fix. On an office desk with no TB-only accessories, UDZ can skip those extra parts. On a desk that has to keep a TB drive, TS4 may be worth the adapters, since UDZ cannot provide that storage connection. Check the exact resolution and refresh support of each adapter instead of relying on the dock’s display headline.
How we worked this out
Direct HDMI on one side, TS4’s documented active DP-to-HDMI requirement on the other. No adapter price, universal refresh support or guarantee that any USB-C video cable works is invented.
A work laptop and a personal Mac may each need their own monitor wiring
Through its MST design, UDZ can suit a supported Windows setup with more than two screens. A personal Mac sharing that desk will not get the same display count. Supported dual-screen use on a Mac needs one output from each UDZ group, and a basic M1 or M2 laptop is still limited to one native external screen. If both laptops use only two screens and a TB drive, TS4 may be the more useful arrangement. When the Windows machine really does use the extra displays, UDZ earns its place at that desk, but plan around the Mac’s smaller usable screen set before you buy. Neither dock is a hardware KVM, so switching hosts is a separate step and attached storage has to be removed safely.
How we worked this out
UDZ’s Windows MST and Mac output-group behavior is applied to a desk shared by alternating work and personal computers. TS4 keeps its TB expansion. There is no universal four-screen Windows promise and no claim of automatic switching.
Option A
CalDigit, TS4-US 500971
CalDigit TS4
The dock has to hold a Thunderbolt-only drive or another verified TB accessory, in addition to a supported screen plan.
- Best for
- The dock has to hold a Thunderbolt-only drive or another verified TB accessory, in addition to a supported screen plan.
Facts we checked
- Downstream TB expansion: Two TB4 ports
- Fixed monitor outputs: One DisplayPort 1.4, no HDMI
- Mac display arrangement: Native host limit applies
- Certified laptop power: 98W
Option B
Plugable, TBT4-UDZ
Plugable TBT4-UDZ
Your current HDMI or DP monitors can plug in directly, and nothing needs a downstream TB connection.
- Best for
- Your current HDMI or DP monitors can plug in directly, and nothing needs a downstream TB connection.
Facts we checked
- Downstream TB expansion: None
- Fixed monitor outputs: Two HDMI and two DisplayPort, in two output groups
- Mac display arrangement: Native host limit, with one output per group for dual Mac use
- Certified laptop power: 98W
Spec by spec
Where they really differ
| Spec | CalDigit TS4 | Plugable TBT4-UDZ | In practice |
|---|---|---|---|
| Downstream TB expansion | Two TB4 ports | None | A drive or interface you already own can settle the purchase before the count of monitor sockets does. |
| Fixed monitor outputs | One DisplayPort 1.4, no HDMI | Two HDMI and two DisplayPort, in two output groups | UDZ lets you keep your HDMI cables, while TS4 needs compatible conversion for those screens. |
| Mac display arrangement | Native host limit applies | Native host limit, with one output per group for dual Mac use | Four video sockets do not make four independent streams on a Mac. |
| Certified laptop power | 98W | 98W | A laptop that draws more power may still need its original charger with either dock. |
| Network and cards | 2.5GbE with PCIe host requirement, UHS-II readers | 2.5GbE and UHS-II readers | Both docks share these interface classes, which do not settle the TB-accessory versus fixed-video choice. |
Trade-offs
What each pick costs you
With CalDigit TS4
- For that conversion CalDigit requires an active DP-to-HDMI adapter. Count the correct cables or adapters in the full cost of the desk.
With Plugable TBT4-UDZ
- A Thunderbolt-only drive needs a suitable laptop port or some other verified way to connect. Ordinary USB-C data cannot replace it.
Change of plan
When the answer changes
A verified TB-only peripheral is the part of the setup that cannot change
Go with CalDigit TS4. TS4 provides downstream TB connectivity, which UDZ lacks.
What is missing is direct HDMI or a qualified Windows multi-screen plan
Go with Plugable TBT4-UDZ. UDZ can do without video adapters and supply the supported screen routes.
Decision guide
Before you buy
Screens and existing accessories should keep working, and the dock with more screen outputs should not turn out to have no place for a Thunderbolt-only device.
What this page can’t tell you
- Nothing here ranks the docks on audio latency, file speed or reliability. Neither dock gets around native Mac limits, and neither supplies 140W host charging. Having a socket for a peripheral does not certify full compatibility.
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 |
|---|---|---|---|
| CalDigit TS4 |
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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.
CalDigit TS4
The dock has to hold a Thunderbolt-only drive or another verified TB accessory, in addition to a supported screen plan.
You want several USB-A accessories to stay plugged in directly, and a DisplayPort screen you already own fits the fixed output.
See price & reviews on AmazonPlugable TBT4-UDZ
Your current HDMI or DP monitors can plug in directly, and nothing needs a downstream TB connection.
A verified Windows host depends on the supported MST screen layout, while a Mac has to stick to the documented separate output groups.
See price & reviews on AmazonEach link opens in a new tab.
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