IRQ holder for PCI steering ?

[skuz]

What is that ? Someone asked me about it, but I really didn't know what to answer...

[BFlurie]

Offhand, it's a necessary addition for any PCI-slot device that use the interrupts 9,10, or 11 (ISA cards using one of these interrupts don't need it). Why it's necessary, I don't know. Try searching Google.com for that phrase.

[surrealchereal]

Windows can dynamically assign or "steer" PCI bus IRQs to PCI devices
ISA devices cannot share an ISA IRQ; however, multiple PCI devices can share a PCI IRQ. On computers that use a PCI bus, the 16-standard IRQs can be programmed to either PCI or ISA mode. An IRQ cannot be programmed for both modes at once.
How IRQs Are Assigned to PCI Devices
is the BIOS assigns IRQs to PCI devices. With OSR2 and Windows 98, Windows 98 Second Edition, and Windows Me, if PCI bus IRQ steering is disabled in Windows the BIOS assigns IRQs to PCI devices, but if PCI bus IRQ steering is enabled, Windows assigns IRQs to PCI devices. When IRQ steering is enabled the BIOS still assigns IRQs to PCI devices and, even though Windows can change these settings, it generally does not.

This is a pretty interesting article I read it a while ago,, I had problems with it... http://www.sysopt.com/forum/smile.gif
more at;
http://support.microsoft.com/support/kb/articles/q182/6/04.asp?LN=EN-US&SD=gn&FR=0&qry=IRQ%20holder%20for%20PCI%20steering%20&rnk=9&src=DHCS_MSPSS_gn_SRCH&SPR=W98