Intel 440GX ユーザーズマニュアル

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Intel
®
 440GX AGPset Platform Reference Design
A-4
Intel
®
 440GX AGPset Design Guide
Power Connectors Front Panel Jumpers
32
This page shows the system ATX power connector, hardware reset logic, and standard chassis 
connectors for the hard disk, power LEDs, and speaker output. Included on this page are the dual-
color LED circuit required to indicate the system state (either ON, OFF, or any of the suspend 
states), the 6-pin optional ATX connector, and the Wake-On-LAN header. Note: a CPU Fan Header 
is required for the Intel Boxed processor.   The dual-color LED circuit is also used to reduce the 
voltage going to the power supply fan, thus decreasing its speed and quieting the system.
Pull-up and Pull-down Resistors
34-35
These pages show pull-up and pull-down resistors for PCI signals, PIIX4E, Slot 1(CMOS), ISA, 
and AGP signals. Also shown are spare gates.
Decoupling  Capacitors
36-37
Decoupling Caps
38
These pages show de-coupling capacitance used in these schematics as well as the voltage dividers 
used to provide the GTL reference voltage.
Hardware system manager
39
The LM79 is a hardware system monitor. It monitors voltage regulation, fan RPM and stores POST 
codes. The device can be accessed via the X-Bus bus or through the PIIX4E SMBus interface. Note 
the voltage level translation circuitry between the 5-Volt LM79 and the rest of the 3.3-Volt SMBus.  
Revision History
40
Changes made to the schematics are listed here underneath the revision where they first appeared 
and by page number.