How to disable ACPI? (give my back my IRQ's !)

[Eratosthenes]

To the Anand faithful -

I?ve tried shutting off ACPI about five different ways and Windows still won?t give me control of my own IRQ?s. The two main shots were shutting off PCI sharing in Windows, and disabling ?ACPI function? in my bios.

Apparently it?s the source of some major system instability (various video woes and freezing only while browsing or another situation with the sound card) with everything piled on IRQ 11. (and I've read the FAQ) I?ve got two free IRQ?s for goodness sakes and I?d like to use them, but I just can't seem to be able to switch around IRQ's in windows like I have on some older machines. There?s still some ACPI/PCI sharing stuff in the system devices box, so it doesn?t appear to be entirely gone. I?d prefer not to go through another 98se install to get rid of ACPI, if indeed it would given how tenacious the thing is.

How can I get control over my IRQ?s?

I?ve tried setting them manually in the bios, but that doesn?t seem to have an effect.


Separate (related) problem. I don?t have any USB devices, so I disabled ?assign IRQ to USB? in the bios, but there?s still a ?USB hub? taking up an interrupt. Any ideas on how to shut that one down?

Thanks so much for helping. It will be great to have this solved before I go back to school.

Chris


(P.S. I wouldn't mind using it if it worked, but at this point I just need to eliminate ACPI as at least a source of the instability.)

Win 98 SE on an AK31 rev 2

 

[AndyHui]

Please read the FAQ: ACPI vs APM

 

[LiLithTecH]

You can try disabling the way Win98SE looks at the IRQ's which will
probably do what you are after.

Goto:

CONTROL PANEL\ SYSTEM \ DEVICE MANAGER \ PCI BUS \ IRQ STEERING
and uncheck the "Get IRQ table using ACPI Bios" box.

 

[JustinLerner]

In Windows 98 it may be possible to change the IRQ's that devices use by moving the PCI device to another slot on your motherboard, or possibly changing the IRQ used per slot in BIOS. In Windows 2000/XP this will not work, although sometimes switching slots will work (because of the way devices are enumerated per slot).

Even though you disable an IRQ for USB or video they will often still be assigned by the OS. USB is low bandwidth, so it won't cause problems if your USB shares an IRQ with your soundcard or modem or even NIC. I wouldn't let your videocard share an IRQ with anything else, because whether APM or ACPI is used, they still time slice the shared IRQ between active (in use) devices because this is the way the I/O-PIC [or APIC for multiple cpu's] works. Installing Windows 9x/ME with, "setup /p j" forces ACPI to be enabled, but I believe by default, APM is enabled unless your motherboard BIOS is set to ACPI.

In Windows 2000/XP to change from ACPI to APM or vice versa requires a reinstallation of the OS after changing the BIOS to ensure the correct type of installation. (F5 or F6 is the option on the first setup screen when asked for SCSI drivers for Windows 2000/XP).