PCI STEERING? &IRQ SETTING

IRQ SETTING #10 BOTH HOLDER FOR PCI STEERING &MODEM ARE ON IRQ 10 IN SYS PROPERTY>CONTROL PANEL> DEVICE MANAGER> COMPUTER PROPERTIES.
ALSO W/COMPUTER PROPERTIES ON #14 SIS IDE CONTROLLER&SIS PCI IDE CONTROLLER DO THEY BOTH BELONG TOGETHER LIKE THIS. STATED WITH MODEM PROBLEMS WAS TOLD MODEM NEEDS TO BE ON OWN PRIVATE PORT?