Intel D975XBX2 - Desktop Board Motherboard, Specification

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Technical Reference
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2.7.2.4.1 Hard Drive Activity LED Header [Orange]
Pins 1 and 3 [Orange] can be connected to an LED to provide a visual indicator that
data is being read from or written to a hard drive. Proper LED function requires one of
the following:
• A Serial ATA hard drive connected to an onboard Serial ATA connector
•
An IDE hard drive connected to an onboard IDE connector
2.7.2.4.2 Reset Switch Header [Blue]
Pins 5 and 7 [Blue] can be connected to a momentary single pole, single throw (SPST)
type switch that is normally open. When the switch is closed, the board resets and
runs the POST.
2.7.2.4.3 Power/Sleep LED Header [Green]
Pins 2 and 4 [Green] can be connected to a one- or two-color LED. Table 30 shows the
possible states for a one-color LED. Table 31 shows the possible states for a two-color
LED.
Table 30. States for a One-Color Power LED
LED State Description
Off Power off/sleeping
Steady Green Running
Table 31. States for a Two-Color Power LED
LED State Description
Off Power off
Steady Green Running
Steady Yellow Sleeping
NOTE
The colors listed in Table 30 and Table 31 are suggested colors only. Actual LED colors
are product- or customer-specific.
2.7.2.4.4 Power Switch Header [Red]
Pins 6 and 8 [Red] can be connected to a front panel momentary-contact power
switch. The switch must pull the SW_ON# pin to ground for at least 50 ms to signal
the power supply to switch on or off. (The time requirement is due to internal
debounce circuitry on the board.) At least two seconds must pass before the power
supply will recognize another on/off signal.