PCIe expansionProduct link
StarTech Four-controller USB 5Gbps card
PEXUSB3S44V
Give bandwidth-sensitive USB instruments separate host controllers.
- Interface
- PCIe x4
- Format
- Standard height + low-profile bracket
PCIe / ASUSHARDWARE EDIT
Category illustration · not a product photograph
PCIE EXPANSION / ThunderboltEX 4
ASUS ThunderboltEX 4 expansion card
Add two Thunderbolt 4 connections to a supported ASUS motherboard with the required header.
IN YOUR WORKFLOWThunderbolt workstation expansion
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THE DETAILS THAT MATTER
At a glance.
- Brand
- ASUS
- Model
- ThunderboltEX 4
- Interface
- PCIe 3.0 x4
- Form factor
- Internal PCIe card
- Ports
- 2 USB-C Thunderbolt 4
- Link rate
- 40 Gbps
- Controller
- Intel JHL8540
- Display input
- 2 Mini DisplayPort
- Charging
- Up to 100 W on Type-C 1
Direct PCIe evidence
Debug the controller’s PCIe side first.
ASUS ThunderboltEX 4 expansion card is a PCIe host controller. The workbench can inspect its host connection while USB peripherals, power delivery and port behavior remain separate checks.
- Confirm the required slot, auxiliary power, motherboard headers and firmware support. Identify the controller’s PCI address on the Linux host.
- Import its collector JSON into the workbench. Review enumeration, driver binding, resources and current versus maximum PCIe link values.
- If relevant errors appear, add the controller’s AER or IOMMU log lines and compare a known-good capture. Test downstream ports and peripherals with their supported operating-system tools.
Header7F inspects PCIe evidence. It does not enumerate USB devices, negotiate USB4/Thunderbolt authorization, test power delivery or certify a cable’s data rate.