How many IRQ settings will Windows XP have?

[stano]

It be great if they would add some in order to avoid conflicts..

 

[sandshoe]

The number of IRQ's available has absolutely nothing to do with the OS. It's hardware dependent. All motherboards have 15 IRQ's and that's it. Complain to the motherboard makers if you want more.

 

[NickM]

yeah, you're right. More and more hardware types and models introduced every week, but we really don't have more ways to connect them to our boxes than we did couple years ago.

 

[eburies]

are there any mobo manufactures planning on expanding how many irqs the next generation of mobos will have, or are they expecting devices such as USB, Firewire, and SCSI to be the new way to connect devices

 

[jasen]

That's exactly what they expect. They're also taking advantage of bus mastering and IRQ sharing in newer devices, so running out of IRQ's isn't as much a problem as it used to be.

 

[NickM]

<font color=green><i> "...All motherboards have 15 IRQ's and that's it. " </i></font color=green>

I thought there are 16 IRQs in today's PCs, numbered from 0 to 15.
????

 

[sandshoe]

2/9 Are the same IRQ. There are actually 2 IRQ controllers each with 8 IRQ's connected via IRQ 2/9. If I remember correctly the original XT's or AT's had only 1 IRQ controller at the time, so they just bunged a second one on there to get up to 15.

 

[NickM]

Yeah, I know, it’s either impossible to assign anything to IRQ2 (used by Programmable Interrupt Controller), or anything assigned is actually handled on IRQ9. If assign both, a conflict will arise. This leaves 15 IRQs to work with, in theory. In practice, there are fewer because some IRQs are used by system timer and clock, the COM and LPT (if not disabled), FDD and HDD controllers, the math processor (even if you don’t have one, the IRQ13 isn’t wired in, can’t use it), PS/2 mouse (may be able to reclaim). This setup leaves with just four IRQs available for use, most of them are of high range above IRQ7 that may not be assignable with some types of hardware.

 

[sandshoe]

I usually just disable both my serial ports, leaving IRQ 3/4 free for something else.

 

[NickM]

Yeah, those who knew have already forgotten what a serial printer is. And others begin to forget about serial mice or parallel printers and scanners. And what serial and parallel ports are for. Don't think that many of us buy an external modem.