Intel Pentium III Processor/840, Manual, Page: 46 / 151

4-10 Intel
®
Pentium
®
III Processor/840 Development Kit Manual
Hardware Reference
Table 4-19 shows the system state changes with contact closure between SW_ON and
FPPWR_ON. Momentary contact closure between FP_RESET and Ground will initiate a complete
system reset.
4.8.10 Processor Fans
Connections for thermal solution fans for the processors are located at J2N1 and J2R1.
Table 4-21 shows the signals assigned for the auxiliary fan connectors.
4.8.11 Chassis Fans
There are six headers provided for additional chassis fans. The fan connectors are: J11A1, J11A2,
J11B1, J1T1, J1T2, J1T3.
Table 4-21 shows the signals assigned for the chassis fan connectors.
Table 4-19. System State Changes Between SW-ON and FPPWR_ON
System State Contact Closure SW_ON to Ground Result
Off Any duration System Power On
On <4 seconds System sleep
On >4 seconds System Power Off
Sleep <4 seconds System Wake-up
NOTE: Power management must be enabled in the BIOS setup. Operating System
Power Management features may change the functionality listed above.
Table 4-20. Processor Fan Connector Pinouts (J2N1, J2R1)
Pin Signal Name
1 Ground
2 +12 (FAN_CTL)
3 Tachometer (FAN_M)
NOTE: Fan_CTL gates the +12 V allowing each fan to be turned on and off by ACPI software for power
management and noise reduction purposes.
Table 4-21. Auxiliary Fan Connector Pinouts (J11A1, J11A2, J11B1, J1T1, J1T2, J1T3)
Pin Signal Name
1 Ground
2 +12 (FAN_CTL)
3 Tachometer (FAN_M)
NOTE: Fan_CTL gates the +12 V allowing each fan to be turned on and off by ACPI software for power
management and noise reduction purposes.