Intel 440GX - Manual (Page 97)

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.