Intel Xeon User Manual

Design Guide 205
Schematic Checklist
PCIXCAP • Conventional PCI cards connect this pin
directly to ground.
PCI-X 133 cards connect PCIXCAP to ground
through a 0.01
µF ± 10% capacitor to provide
an AC signal return path.
PCI-X 66 cards connect PCIXCAP to ground
through a 10 k
Ω ± 5% resistor in parallel with
a 0.01
µF ±10% capacitor to provide an AC
signal return path.
• If implementing hot plug, PCIXCAP should be
pulled up to VCC3.3 through an 8.2 k
Ω ± 5%
resistor.
• See PCI-X Specification 1.0
recommendations for PCIXCAP
connection.
PA_133EN • Enable PCI-X at 133 MHz for PCI Bus A. This
pin, when high, allows the PCI-X segment to
run at 133 MHz when PA_PCIXCAP is
sampled high. When low, the PCI-X segment
runs only at 100 MHz when PA_PCIXCAP is
sampled high.
• For 133 MHz (max) PCI-X capable slot:
8.2 k
Ω ± 5% pull-up resistor to VCC3.3.
• For 100 MHz (max) PCI-X capable slot:
8.2 k
Ω ± 5%pull-down resistor to ground.
• Active only if PA_PCIXCAP pin
is high.
PB_133EN • Enable PCI-X at 133MHz for PCI Bus B. This
pin, when high, allows the PCI-X segment to
run at 133 MHz when PB_PCIXCAP is
sampled high. When low, the PCI-X segment
runs only at 100 MHz when PB_PCIXCAP is
sampled high.
• For 133 MHz (max) PCI-X capable slot:
8.2 k
Ω ± 5% pull-up resistor to VCC3.3.
• For 100MHz (max) PCI-X capable slot:
8.2 k
Ω ± 5% pull-down resistor to ground.
• Active only if PB_PCIXCAP pin
is high.
IDSEL • The series resistor on IDSEL should be 100
Ω. • This has changed from the
PCI-X 1.0 Specification. There
is a specification change that
allows for values other than the
original 2 k
Ω value.
3.3Vaux • Leave this as unconnected on the PCI slots. • The P64H2 does not support
PCI bus power management.
PCI-X Specific Interface
PCIXCAP • Conventional PCI cards connect this pin
directly to ground.
PCI-X 133 cards connect PCIXCAP to ground
through a
0.01 µF ± 10% capacitor to provide an AC
signal return path. PCI-X 66 cards connect
PCIXCAP to ground through a
10 k
Ω ± 5% resistor in parallel with a 0.01 µF ±
10% capacitor to provide an AC signal return
path.
• If implementing hot plug, PCIXCAP should be
pulled up to VCC_3.3 through an 8.2 k
Ω
resistor. If not implementing hot plug, this
signal does not require a pull up or pull down.
• See
PCI-X Specification
recommendations for PCIXCAP
connection.
Table 13-4. Intel
®
P64H2 Schematic Checklist (Sheet 2 of 5)
Checklist Items Recommendations Comments

Intel Xeon Specifications

General

Brand	Intel
Model	Xeon
Category	Processor
Language	English