Intel® 41110 Serial to Parallel PCI Bridge Design Guide 35
PCI-X Layout Guidelines
8.5 PCI-X Topology Layout Guidelines
The PCI-X Addendum to the PCI Local Bus Specification, Revision 1.0a compliant, recommends
the following guidelines for the number of loads for your PCI-X desi gns. Any deviation from t hese
maximum values requires close attention to layout with regard to loading and trace lengths.
8.6 41110 Layout Analysis
The following sections describes layout recommendations based on the signal integrity analysis.
This analysis was conducted using the following parameters:
Card stack up: 60 +/- 15% single-ended impedance
Driver Model 41110 IBIS
Receiver Model: generic models for PCI-X and PCI
Driver Package Model: 41110 Model
Cross talk and ISI impact on timing were not modeled
Table 9. PCI-X Slot Guidelines
Frequency Maximum Loads Maximum Number of Slots
66 MHz 8 4
100 MHz 4 2
133 MHz 2 1