Sabrent’s SB-TB4K is a Thunderbolt 4 KVM switch for sharing a display and peripherals between two computers. It advertises up to 8K at 60Hz, but that maximum depends on Display Stream Compression (DSC), compatible host and display hardware, and the right adapter and cable. It is a specialized Thunderbolt switch—not a universal USB-C KVM or a full-featured dock.
What the SB-TB4K is—and when it launched
Sabrent’s Thunderbolt 4 KVM Switch, model SB-TB4K, connects two host computers to a shared set of Thunderbolt and USB peripherals. It switches the active Thunderbolt connection, so the selected computer can use the connected display and accessories. Contemporary launch coverage dated the product announcement to June 25, 2023; it is not a new 2026 launch. BetaNews’ June 2023 coverage reported on the product.
Sabrent lists Windows and macOS support. The practical question is not just which operating system a computer runs, but whether its port and implementation meet Sabrent’s host requirements.
Ports, power, and what comes in the box
| Feature | Sabrent’s listed specification |
|---|---|
| Host connections | Two Thunderbolt 4 host connections for two computers |
| Thunderbolt ports | Three total, up to 40Gbps |
| USB-A ports | Four USB 3.2 Gen 2×1 ports, up to 10Gbps |
| Charging | Up to 60W USB Power Delivery 3.0 bypass to a connected laptop; USB-A and Thunderbolt ports also support BC1.2 charging up to 5V/2.4A |
| Display claims | One display up to 8K/60Hz with DSC; up to 8K/30Hz without DSC 1.2; up to 4K/120Hz or 4K/144Hz with DSC; or two displays up to 4K/60Hz on compatible systems |
| Included items | SB-TB4K switch, integrated 70cm Thunderbolt 4 cable, 24V/5A power adapter, user manual, and warranty card |
| Size and construction | Aluminum body; 6.3 × 2.76 × 0.71 inches; 17.7 ounces |
| Warranty | One year, extendable to two years by registering within 90 days |
These specifications are from Sabrent’s SB-TB4K product page. It does not list built-in Ethernet, HDMI, DisplayPort, audio, or a card reader. To add those connections, you would need peripherals or a downstream dock, which adds cost and another compatibility variable. Some display setups also require a Thunderbolt-to-DisplayPort or USB-C-to-DisplayPort adapter; longer or replacement cables may need to be certified for the intended Thunderbolt bandwidth.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →#1 Best Overall
- CONNECT & SWITCH : The sleek Sabrent Thunderbolt 4 KVM Switch (SB-TB4K) is here, ready to help you share your Thunderbolt and USB devices between two host computers with high resolution display output. It’s an easy way to maximize your productivity, for work or for play.
- THUNDERBOLT 4: Connect up to three Thunderbolt 4 devices with transfer speeds of up to 40Gbps. This switch also has four USB Type-A ports for other devices like keyboards, mice, and external storage, with transfer speeds of up to 10Gbps (USB 3.2 Gen 2x1). All seven ports support BC1.2 and charge up to 5V@2.4A for added convenience.
- BIG DISPLAY: Seamlessly switch between two computers or DisplayPort Alternate Mode (DP Alt Mode) capable USB-C devices with output to an external display. Enjoy up to 8K@60Hz (30Hz without DSC1.2) or 5K@60Hz output on a DisplayPort-capable display. Additionally, when using two screens, it will support up to 4K@60Hz, allowing you to maximize your productivity and create a stunning visual experience in your workspace. Reclaim your workspace in style.
- READY TO WORK: Manufactured from high-quality aluminum to withstand impact and dissipate heat to improve its lifespan. Arrives with an integrated cable (70cm) and clear LED indicators for source and PD statuses. Includes a 24V/5A power adapter to support PD3.0 charging at up to 60W for laptops and other devices.
- SABRENT SUPPORT: The SB-TB4K is designed for Windows and macOS computers but may work with other compliant devices. Please visit the our website to register your product and extend your warranty. Direct any questions to our excellent technical support team.
What “8K/60Hz” requires
The 8K/60Hz figure is a conditional maximum, not a guarantee for every computer and monitor. Sabrent specifies 8K/60Hz with DSC and 8K/30Hz without DSC 1.2. DSC is a display-compression feature; the host, graphics hardware, display, connection path, and any adapter must all support the required mode. Sabrent also notes that an appropriate Thunderbolt 4 or USB-C-to-DisplayPort dongle may be needed.
- Host: It must meet Sabrent’s Thunderbolt or supported DisplayPort Alt Mode requirements, and its GPU must support the chosen resolution and refresh rate.
- Display: The monitor must accept the target mode, and its input may need to be configured for maximum bandwidth.
- DSC and connection path: For 8K/60Hz, DSC support must be available where required. The adapter and cable must also support the necessary DisplayPort mode.
- Display count: One 8K display and two 4K displays are separate configurations with different bandwidth and host limitations.
For other single-display ceilings, Sabrent lists up to 5K/60Hz or 6K/60Hz depending on the host and display, and up to 4K/120Hz or 4K/144Hz with DSC. Actual results depend on the complete signal path, not just the switch.
Two displays are possible, but system support matters
Sabrent advertises up to two 4K/60Hz displays on compatible systems and lists EDID and MST support. That does not mean every connected Mac or Windows PC will drive two external screens through the same setup. The host GPU, number of display streams it exposes, operating-system behavior, and any downstream dock or adapter all affect the outcome. Apple silicon Mac models differ in how many external displays they support, and MST behavior can vary between macOS and Windows.
Rank #2
- Compatibility and Bandwidth Limits: Connect a compatible USB-C, USB4, or Thunderbolt 4 dock with a detachable host cable. A connection to an 80Gbps dock is limited to 40Gbps through the switch. Docks with built-in, non-detachable host cables are not supported and cannot be connected using a USB-C coupler. The end-to-end built-in cable path already reaches 1.8m (1m + 0.8m), so do not use a USB-C extension cable.
- 40Gbps USB C Switcher for 2 Laptops: Share one compatible monitor or docking station between two MacBook Pro, MacBook Air, or Windows laptops. This high-speed USB C switch provides connection bandwidth of up to 40Gbps for external storage, dock peripherals, video conferencing equipment, and other connected USB devices.
- High-Resolution USB-C Video Switching: Display video up to 8K@60Hz, 6K@60Hz, or 4K@240Hz with compatible equipment and DSC where required. Supports USB-C and Thunderbolt monitors, including Apple Studio Display; Dell U2725QE, U3225QE, U3224KB, and U4025QW; ASUS ProArt PA32QCV; Samsung ViewFinity S9; LG UltraFine 32U990A-S; and MSI MPG 321URX. Maximum resolution and refresh rate depend on the complete setup.
- Share a USB4 or Thunderbolt Dock: Connect a compatible USB-C, USB4, Thunderbolt 3, or Thunderbolt 4 docking station with a detachable host cable to share its displays, keyboard, mouse, storage, Ethernet connection, and other peripherals between two laptops. Compatible models include CalDigit TS4 and TS3 Plus; Plugable TBT4-UDZ and TBT3-UDZ; Lenovo ThinkPad Universal TB4 40B0; OWC 11-Port Thunderbolt 4 Dock; Anker 778; Satechi Thunderbolt 4 Dock; Kensington SD5780T; and Cable Matters 107054.
- 140W Power Delivery Pass-Through: Charge the selected laptop at up to 140W when the connected monitor or docking station provides compatible USB Power Delivery. This USB-C KVM switch passes charging power to the active laptop only; actual power depends on the power source and receiving laptop.
Third-party user reports raise questions about multi-monitor behavior, but they do not establish a universal result for all host and display combinations. Check the limits of both computers before buying if dual-monitor output is essential.
Check host certification before connecting it
Sabrent says the SB-TB4K is intended for Thunderbolt-certified host systems and warns that using uncertified devices can cause permanent damage. A USB-C connector alone does not establish Thunderbolt compatibility: ordinary USB 3.x, USB-C charging, and USB4 should not automatically be treated as equivalent to a certified Thunderbolt implementation. A desktop may also depend on motherboard support, a Thunderbolt add-in card, a motherboard header, and BIOS configuration.
Users have reported damage to MacBook ports, motherboards, or other Thunderbolt hardware. In a December 27, 2023 support-forum response, Sabrent acknowledged an issue involving uncertified devices and said a fix had been applied to units sold at that time, while maintaining that certified systems were the intended hosts. That is Sabrent’s statement, not an independent safety certification or a guarantee that every compatibility problem is resolved. A third-party teardown and review also described issues with select non-conformant PC motherboards, including the MSI MEG Z690i Unify. These reports warrant caution but do not establish a failure rate or prove that every SB-TB4K is unsafe. Sabrent’s support discussion and the third-party teardown and review describe the respective concerns.
Rank #3
- 【USB C KVM Switch 3 Monitors】This 12‑in‑1 USB‑C KVM switch docking station enables seamless triple‑monitor switching between 2 laptops. It shares USB peripherals via 10Gbps USB‑C/A and two 5Gbps USB‑A ports, and features SD/TF card reader slots. It delivers 50W PD charging and Gigabit Ethernet to both laptops at the same time. Conveniently toggle your triple‑monitor setup between your personal and work laptop.
- 【 Break Display Limits for Apple Silicon Macs 】Traditional 3 monitor KVM switches struggle with multi‑screen extension on Apple Silicon Macs. This DisplayLink KVM switch unlocks true extended display functionality for M1/M2/M3/M4/M5 Mac processors. It works seamlessly with Windows 10+ and macOS 11+, supporting mirror (AAAA) as well as extended display modes (ABBB/ABBC/ABCD).
- 【 Strong Compatibility 】 DisplayLink 3 monitors KVM switch docking works with USB4, Thunderbolt 5/4/3, full‑featured USB‑C Windows laptops,Apple Silicon Mac, MacBook, MacBook Neo; supports Win10+, ChromeOS 100+, macOS 11+, Ubuntu. NOTE: Not compatible with Linux/Unix.
- 【Important Notice】1.This USB‑C triple‑monitor KVM switch requires DisplayLink driver installation for full functionality. You may use the included driver disk or download the driver from the official DisplayLink website. 2. An Intel Core i7 or newer CPU and a minimum of 16 GB RAM are recommended for optimal performance.
- 【Triple 4K@60Hz Simultaneous Output】This thunderbolt USB C KVM switch supports 3-monitor simultaneous output (max 4K@60Hz), backward compatible with lower resolutions.Note: Use included Thunderbolt 4 cable (40Gbps) for laptop-KVM connection; HDMI/DP cables ≤1.5m recommended. Monitor A/B: HDMI-only; Monitor C: DP/HDMI (select one).
- Confirm the exact computer or motherboard’s Thunderbolt certification and implementation rather than relying on its USB-C port shape.
- For an unusual or uncertified host, ask Sabrent to confirm the unit’s firmware or revision and compatibility before connecting it.
- For a desktop add-in card, check the motherboard, BIOS, and header requirements as well as the card itself.
How to connect the switch
- Confirm both computers use host connections that meet Sabrent’s requirements. Make sure their GPUs and operating systems support the display arrangement you want.
- Connect the included 24V/5A power adapter to the SB-TB4K.
- Connect each computer to one of the two Thunderbolt 4 host inputs.
- Connect the monitor to a downstream Thunderbolt port. Add a suitable Thunderbolt-to-DisplayPort or USB-C-to-DisplayPort adapter if your monitor’s input requires one.
- Connect shared keyboard, mouse, storage, and other accessories to the switch’s Thunderbolt and USB-A ports.
- If adding a downstream dock, validate that exact dock and connection chain; do not assume every port on it will work through the KVM.
- Wake or start both computers, then use the switch control to select the host you want.
- On the selected computer, verify the display, keyboard, mouse, and storage are available. Set and confirm the desired resolution and refresh rate in the operating system.
What to check when something does not work
The display reaches only 8K/30Hz
Check whether DSC is supported and enabled, whether the host GPU supports 8K/60Hz, and whether the monitor input is set to its highest-bandwidth mode. Also verify that the adapter, cable, and any dock in the path support the required display mode; one lower-capability link can limit the whole chain.
The second monitor does not appear
Check how many external displays the host supports and whether it exposes the required display streams. Mac model limits, MST behavior, a downstream dock, or a non-Thunderbolt host connection may prevent the advertised two-display configuration from working.
USB devices disappear after switching
A host may still need to authorize the Thunderbolt connection, or a peripheral may need to re-enumerate after the switch. A downstream hub can also introduce compatibility problems. In one Sabrent support thread, a user reported that USB-A or non-Thunderbolt USB-C ports on a downstream hub had no data through the KVM chain; Sabrent suggested replacement if the issue proved hardware-specific. This is a reported configuration, not proof that all downstream hubs fail.
Rank #4
- 4K@60Hz Full HD Resolution: Enjoy crystal-clear visuals with native 3840*2160 resolution, delivering sharper, brighter, and more vibrant images for an immersive viewing experience. This projector with KVM Function is perfect for creating a stunning home theater or bedroom projector setup
- Dual 4K@60Hz Extended Display for Mac & PC: Delivers stunning dual 3840*2160@60Hz extended display output for Mac systems (including M1, M2, M3, M4 chipsets like MacBook, MacBook Air/Pro, and Mac Mini) and Windows PCs. Unleash the full visual potential of your high-end devices—experience crystal-clear detail far beyond 1080p or 1440p. Please Note: Does not support Power Delivery (PD) charging. Driver installation is required before use.
- Broad Monitor Compatibility: HDMI, DP, and DVI: Our USB C KVM switch dual monitor offers flexible video output options with both HDMI and DisplayPort ports. It seamlessly connects to a wide range of monitors, including those with HDMI, DisplayPort, or DVI inputs. Please Note: Connecting a DVI monitor requires an HDMI-to-DVI cable (not included). For optimal 4K@60Hz performance, we recommend using high-quality cables (under 3 feet/1 meter is ideal) that support DP 1.4 and HDMI 2.1 standards.
- Extensive System Compatibility: KVM switch 2 monitors 2 computers works seamlessly with macOS, Windows, Chrome OS, Linux, and Android devices. Unlock the full functionality of this KVM docking station as long as your device is equipped with a USB-C 3.2 (or higher) port. It's the ultimate all-in-one hub for efficient remote work and powerful home office setups.
- Save Valuable Desk Space & Simplify Your Setup: Replace a tangled mess of cables with just two streamlined 40Gbps USB-C connections to your laptops. The included extension cable for the switch button allows you to discreetly hide the main KVM unit under your desk or behind a monitor, maximizing your valuable desktop real estate and contributing to a cleaner, more organized, and focused workspace.
The laptop charges slowly or not at all
The SB-TB4K provides up to 60W, which may not meet the needs of a gaming laptop or mobile workstation that requires more power. The laptop must also accept charging over its Thunderbolt connection. Keep the laptop’s original charger available if it needs higher wattage or proprietary charging.
The unit feels warm
Sabrent said in its support discussion that the unit can become quite warm and should operate normally in an open-air room. That is the manufacturer’s response, not an independent thermal test. Avoid obstructing ventilation and contact Sabrent if the device behaves abnormally.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Is it worth considering?
The SB-TB4K makes the most sense for someone with two compatible Thunderbolt computers who wants to switch shared Thunderbolt peripherals and a display together. It is less compelling if you only need to change which computer uses a keyboard, mouse, and HDMI monitor.
PC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteBest Value
- Effortless 2-in-1 USB C Switch :Easily control two computers with a single monitor using the Alxum USB C Switch. Perfect for office professionals and gamers who need seamless switching without installing any software. Quickly switch between devices with a wireless remote or the button on the switch itself. Note: Ensure all three connected USB-C devices support DP ALT MODE .
- For USB C Docking Station：①Direct Connected:When the Type-C Male on the switch is directly connected to the Type-c female port of the docking station, the performance can reach the best; ②Connect with Adapter：If your docking station is with pigtail, please use the included USB-C female to female adapter, but please make sure that the length of the docking/hub body pigtail does not exceed 50CM(The specific performance may be related to the performance of your USB or TBT host)
- 20Gbps High-Speed Transmission:Enjoy ultra-fast data transfer up to 20Gbps. Stream videos, transfer files, and play games without lag. Our USB-C switch ensures professional efficiency and reliable teamwork in any work or gaming scenario.
- 8K & 4K High-Resolution Display:Supports up to 8K@30Hz or 4K@144Hz for an immersive visual experience. Compatible with USB-C/Thunderbolt 4 monitors and docks. Note: When connecting dual monitors via a Thunderbolt 4 dock, the maximum resolution is 4K@60Hz. MacOS supports the expansion of ONE 4K@60Hz monitor.
- PD 140W Charging:Provides powerful 140W pass-through charging for laptops, tablets, and phones. Keep your devices fully charged while switching between computers, ensuring safe and reliable power delivery.(Power supply is not included.)
| Consider the SB-TB4K if… | Look at another setup if… |
|---|---|
| You have two Thunderbolt-capable computers and need to share fast Thunderbolt storage or other Thunderbolt peripherals. | Your computers have ordinary USB-C or HDMI/DisplayPort but no supported Thunderbolt host connection. |
| You value switching a shared Thunderbolt workspace, potentially including one high-resolution display. | You need built-in Ethernet, audio, card-reader, or dedicated HDMI/DisplayPort sockets. |
| Up to 60W charging suits your laptop. | Your laptop needs 100W or more, or a proprietary high-wattage charger. |
| You can verify host certification and validate the complete display and peripheral chain. | You need a low-cost, straightforward switch for a basic monitor and USB accessories, or cannot verify an unusual desktop implementation. |
A conventional HDMI/DisplayPort KVM paired with a dock for each computer is often a simpler, less expensive route for basic display and USB switching, and it can suit computers without Thunderbolt. It will not provide the same shared Thunderbolt connection or single-link workflow. A separate dock for each computer with the monitor and USB devices switched independently is another option, though it means more cables and can make switching less seamless. A downstream dock attached to the SB-TB4K can add ports such as Ethernet and audio, but it raises the cost and adds another layer to validate.
Price and availability
Sabrent lists the SB-TB4K at $299.99 and specifies a one-year warranty, with an extension to two years available through registration within 90 days. The official product page showed the switch as sold out in the latest retrieved listing, so the listed price is not a promise of current stock or a street price. Check Sabrent’s product page for its current listing.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
