ASRock X79 Extreme9 manual Two USB 3.0 headers on this

USB 2.0 Headers			USB_PWR
(9-pin USB_8_9)				P-9
					P+9
						GND
(see p.12	No. 39)	1					DUMMY
						GND
					P+8
				P-8
(9-pin USB_10_11)			USB_PWR
			USB_PWR
(see p.12	No. 36)			P-11
					P+11
						GND
		1					DUMMY
						GND
					P+10
				P-10
(9-pin USB_12_13)			USB_PWR
(see p.12	No. 34)

Besides six default USB 2.0 ports on the I/O panel, there are three USB 2.0 headers on this motherboard. Each USB 2.0 header can support two USB 2.0 ports.

USB 3.0 Header	Besides two default USB 3.0
(19-pin USB3_4_5)	ports on the I/O panel, there are
(see p.12 No. 18)	two USB 3.0 headers on this
	motherboard. Each USB 3.0
	header can support two USB
	3.0 ports.

(19-pin USB3_6_7)

(see p.12 No. 17)

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