Asus M4N78-AM - Manual (Page 21)

6. USB connectors (10-1 pin USB56, USB78, USB910)
These connectors are for USB 2.0 ports. Connect the USB module cable to any of
these connectors, then install the module to a slot opening at the back of the system
chassis. These USB connectors comply with the USB 2.0 specification that supports up
to 480Mbps connection speed.
Never connect a 1394 cable to the USB connectors. Doing so will damage the
motherboard!
The USB 2.0 module is purchased separately.
7. CPU fan connector (4-pin CPU_FAN)
The CPU fan connector supports cooling fans of 350mA~740mA (8.88W max.).
Connect the CPU fan cable to the CPU fan connector on the motherboard, ensuring
that the black wire of each cable matches the ground pin of the connector.
Only the CPU fan supports the ASUS Q-Fan feature.
DO NOT forget to connect the CPU fan cable to the CPU fan connector. Insufficient air flow
inside the system may damage the motherboard components. It is not a jumper! DO NOT
place a jumper cap on the CPU fan connector.
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