manually changing IRQ's

[Gil Theissen]

with WinXP pro, how do you manually change IRQ's? I was having trouble
with a new modem and I noticed that in Device Manager, the modem, my NIC and
my Display Adaptor were all on IRQ 9. However the box to manually change
'resources, for all three devices was greyed out, even though there were at
least two extra unused IRQ's available..
I finally had to go into the BIOS and disable a COM port. Does XP limit
(or just move) the option to manually chnage IRQ's in devioce Manager?

Thansk -- Gil Theissen

[David Schwartz]

"Gil Theissen" <gilth...@prodigy.net> wrote in message
news:0RTLa.243$rx1.23...@newssvr15.news.prodigy.com...

Are you having some specific problem? WinXP knows what it's doing and
you shouldn't need to mess with IRQs unless something is wrong. If you're
using an ACPI HAL, it should be even less of a problem. (In the device
manager, look under Computer, if it says 'ACPI Multiprocessor PC' or 'ACPI
PC' or anything with ACPI in it, shared interrupts should work just fine.)

DS

[relic]

As predicted, Gil Theissen typed:

IRQ Sharing is managed by ACPI and /usually/ works... but not always. Some
(certainly not all) IRQ conflicts will cause your system to crash.

The most effective way to get rid of IRQ conflicts that cause problems, is to
swap cards around in the PCI Slots. All Sound Cards (or on-board sound), and
some NICs don't behave very well when they are sharing an IRQ with other
devices... look in your motherboard manual to see which slots are shared, and
with what (the 'on-board' devices are shared with PCI slots). XP will
reconfigure itself on the next boot.

The other way is to get rid of ACPI and use APM instead. I don't recommend
this except when you are unable to resolve a conflict _that causes problems_ .
If you change the Device Management "Computer" from an "ACPI Compliant PC" to
a "Standard PC" ACPI is disabled (worse case, it will require a re-install or
repair to get rid of it -- when it asks for you to hit F6 to load SCSI
drivers, hit F7 to force Standard PC). APM can be installed in Add/Remove
Programs; it defaults to "OFF" when installed. Turn it on in the Power
Settings, APM tab.

By using APM instead of ACPI, you can set most of your IRQs. I would first
attempt to resolve the conflict that is causing problems by relocating boards.

--
- relic -
Resident Psychic: alt.os.windows-xp

[Gil Theissen]

Thanks for the replies and especially the tip about switching over to APM.
Turned out that the modem itself was bad. Still, based on my limited
experience with earlier OS's, It certainly was a surprise to see three
different devices on the same IRQ.
Thanks again -- Gil
Theissen

[relic]

As predicted, Gil Theissen typed:

Glad to hear you found it and you're running again.