USB 3.0 19 Pin Male to USB 2.0 9 Pin Internal Adapter Cable – Motherboard Header Converter (15cm) This USB 3.0 to USB 2.0 internal adapter cable allows you to connect a USB 3.0 19 pin motherboard header to a standard USB 2.0 9 pin connector. It provides a practical solution for adapting newer motherboard headers to older front panel USB connections. Designed for internal PC use, this adapter helps maintain compatibility when your case has USB 2.0 ports but your motherboard only provides USB 3.0 headers. It offers a simple and effective way to bridge the gap without requiring additional expansion cards.
eBay