ECS PF4 Extreme User Manual page 16

15. USB3/USB4 (Front USB Headers, 10-1 pin, Yellow)
If the USB ports on the rear panel are inadequate, two USB headers are
available for additional USB ports. The USB header complies with USB
2.0 specification that supports up to 480 Mbps connection speed. This
speed advantage over the conventional 12 Mbps on USB 1.1.
16. 1394A2 (10-1 pin Header, Orange)
Attach the 10-1 pin 1394 cable plug from the device to this connector.
You may also connect a 1394-compliant internal hard disk to this con-
nector.
17. SMB1 (SMBus Header, 6-1 pin)
This connector allows you to connect SMBus (System Management Bus)
devices. Devices communicate with an SMBus host and/or other SMBus
devices using the SMBus interface.
18. CDIN1 (CD In Connector, 4 pin)
Connect CD-ROM or DVD-ROM audio out to the connector.
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