ASUS ThunderboltEX 4 PCIe Card - Dual Thunderbolt 4 Ports

In this review the ASUS ThunderboltEX 4 is evaluated as a niche internal I/O card for desktop builders who need flexible, high-bandwidth connectivity. The card's single biggest selling point is its use of the Intel Thunderbolt 4 JHL 8540 controller and two USB Type-C ports that support up to 40Gb/s bi-directional bandwidth, which makes it suited to users who want to attach high-speed storage, external GPUs, or 8K-capable monitors. The review focuses on real-world compatibility, installation experience, and whether the card delivers the advertised throughput and charging capability.

Key Features

• Intel Thunderbolt 4 controller: The JHL 8540 chip provides the platform-level support required for Thunderbolt 4 and USB 4 performance and device compatibility.
• Two Type-C ports: Dual USB Type-C ports mean a system can host multiple Thunderbolt devices and support daisy-chaining up to five Thunderbolt-enabled devices per port.
• 40Gb/s bandwidth: Each port offers up to 40Gb/s bi-directional bandwidth to accommodate high-speed NVMe enclosures, capture devices, and professional peripherals.
• DisplayPort 1.4 support: Mini DisplayPort IN ports let the card redirect video and support DisplayPort 1.4 monitors up to very high resolutions, suitable for single 8K displays via compatible hardware.
• Quick charge support: The card can provide up to 100W quick charge power delivery to compatible devices, useful for powering laptops and large peripherals from the Type-C port.
• ASUS motherboard requirement: The card is designed to work with supported ASUS motherboards to enable the full feature set and firmware-level compatibility.

Who It's For

The ThunderboltEX 4 is aimed at creative professionals, power users, and content creators who need high-throughput external connections from a desktop PC, such as external NVMe arrays, Thunderbolt docks, capture cards, or eGPUs. It is also useful for users who want DisplayPort redirection to drive very high resolution monitors from a system without native Type-C display output.

It is not the best choice for users with non-ASUS motherboards or those who want a plug-and-play USB expansion without attention to driver and firmware compatibility. Casual users who only need a few USB ports or modest charging will find cheaper alternatives without Thunderbolt 4 features.

Pros & Cons

Pros

• High performance with the Intel Thunderbolt 4 JHL 8540 controller delivering consistent 40Gb/s bandwidth for demanding peripherals.
• Two Type-C ports with USB 4 support and daisy-chain capability give flexible connection options for multiple Thunderbolt devices.
• DisplayPort 1.4 support allows redirection to very high resolution monitors when combined with compatible inputs.
• Up to 100W quick charge provides substantial power delivery for laptops and accessories from the Type-C port.

Cons

• Only supports ASUS motherboards, which limits compatibility across systems and requires checking motherboard support lists.
• Some customers reported mixed installation and driver experiences, so setup may require troubleshooting on certain systems.

Specifications

Controller	Intel Thunderbolt 4 JHL 8540
Ports	2 USB Type-C (Thunderbolt 4 / USB 4)
Bandwidth	Up to 40Gb/s bi-directional per port
Display Support	DisplayPort 1.4 via two mini DisplayPort IN ports
Power Delivery	Up to 100W quick charge support
Compatibility	Only supports compatible ASUS motherboards

Our Verdict

The ThunderboltEX 4 is a practical upgrade for ASUS-based desktop systems that need professional-grade external connectivity. For users with supported motherboards who require reliable 40Gb/s links, multi-device daisy chaining, and high-resolution display redirection, it represents strong value compared with external docks. Those on non-ASUS boards or who want the simplest possible setup should consider other USB expansion options.

Frequently Asked Questions

Will this card work on non-ASUS motherboards?
It is designed to work only with supported ASUS motherboards, so compatibility on other brands is not guaranteed and likely limited.

Can I use both Type-C ports simultaneously at full speed?
Yes, the card provides Thunderbolt 4 USB 4 support on both Type-C ports with up to 40Gb/s bi-directional bandwidth per port for high-speed devices.

Does the card provide Power Delivery for laptops?
The card supports up to 100W quick charge power delivery to compatible devices, but actual charging performance may vary in real-world conditions.