Asus P8Z77-V PRO/THUNDERBOLT - Manual (Page 52)

2-28 Chapter 2: Hardware information
Chapter 2
7. CPU and chassis fan connectors
(4-pin CPU_FAN; 4-pin CPU_OPT;4-pin CHA_FAN1-3)
Connect the fan cables to the fan connectors on the motherboard, ensuring that the
black wire of each cable matches the ground pin of the connector.
• The CPU_FAN connector supports the CPU fan of maximum 1A (12 W) fan power.
• All the CPU and CHA fans support ASUS Fan Xpert 2 feature.
• If you install two VGA cards, we recommend that you plug the rear chassis fan cable
to the motherboard connector labeled CHA_FAN1-3 for better thermal environment.
Do not forget to connect the fan cables to the fan connectors. Insufficient air flow inside the
system may damage the motherboard components. These are not jumpers! Do not place
jumper caps on the fan connectors!