Intel 440GX ユーザーズマニュアル

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Intel
®
 440GX AGPset Design Guide
3-37
Design Checklist
3.21.1
Design Considerations
The Intel
®
 Pentium
®
 II processor retention mechanism, retention mechanism attach mount 
and heat sink support is an optional support structure for retaining the Slot 1 processor in the 
system during shock and vibration situations. If these Intel enabled retention solutions are 
used, the motherboard keep out zones and mounting hole requirements must be met. See the 
Intel
®
 Pentium
®
 II Datasheet for details.
The Boxed Intel
®
 Pentium
®
 II processor requires the implementation of the heatsink support 
holes for the heatsink support structure as defined in the Intel
®
 Pentium
®
 II Datasheet to 
properly support the Boxed Intel
®
 Pentium
®
 II processor fan/heatsink.
3.22
Electricals
3.22.1
Design Considerations
It is recommended that simulations be performed on the GTL+ bus to ensure that proper bus 
timings and signal integrity are met, especially if the layout guideline recommendations in this 
document are not followed.
It is recommended that simulations be performed to ensure proper timings and signal integrity 
is met, especially if the non GTL+ (CMOS) layout guideline recommendations in this 
document are not followed.
Verify the voltage range and tolerance of your VRM or onboard regulator adequately cover the 
Vcc
CORE
 requirements of the Slot 1 processor(s) is supported.
Verify the maximum current value your VRM or on board regulator can support at Vcc
CORE. 
This should meet the value specified by the VRM 8.2 DC-DC Converter Specification
Verify the voltage tolerance of your VRM or on board regulator at Vcc
CORE. 
This should meet 
the value specified by the VRM 8.2 DC-DC Converter Specification.
Adequate 5V and/or 3.3V decoupling should be provided for all components.
V
REF
 for the AGPset should be decoupled to VTT with 0.001mF capacitors at each voltage 
divider. It should be decoupled to ground, to ensure an even better solution.
It is recommended that AC/DC analysis be performed to determine proper pull-up and pull-
down values.