6 things assigned to IRQ 9 ( >_< ) (1 Viewer)

[Scott L]

I was fiddling around with Word and went to Help > About Microsoft Word. There was this nifty button called System info and it brought up a whole slew of neat stuff. Under Harware settings I clicked Conflicts/Sharing and it showed that 6 things were all on IRQ #9. To confirm this i clicked IRQs and here's what is on that channel:
- Netgear NIC card
- SBLive! Card
- Conextant Video Capture (cheap cap card I just installed, doesn't work)
- TI IEEE1394 Host Controller (prolly why my firewire captures are acting up)
- Microsoft ACPI-Compliant System (?)
- Intel USB Universal Host Controller 2444 (I have been having minor problems with a USB mouse)
Ok now how do assign a different IRQ to each device to hopefully get things working right? Thanks for any help.

 

[Rob Gillespie]

Which OS are you using?

If it's Windows 2000 or XP then this is normal if it got installed in ACPI (default) mode.

Are you suffering and particular problems at the moment? If not, probably best leave things as they are. It's possible to revert the installation back to a Standard PC version (non-ACPI) but it can cause other problems. I myself have had probs with the Soundblaster card. When I install W2K in non-ACPI mode, the problems go away.

 

[Scott L]

ahh ok. I don't really keep up with the times when it comes to little things such as these. I will be doing a fresh XP install soon anyway, hopefully that will help my problems. thx Rob.

 

[Rob Gillespie]

If you want to disable ACPI (and thereby go back to 'normal' IRQ assignment), you need to keep pressing F5 during the first part of the Windows installation routine. It's the bit where you get a line of text at the bottom saying to hit F6 if you want to install third-part drivers. If you keep hitting F5, you'll get some installation options appear. Choose Standard PC and XP will then install without ACPI enabled.

Of course, doing this means you'll lose the standby and hibernate fuctions.

 

[Scott L]

That's all ACPI does? I never use those system standby type functions.

 

[Rob Gillespie]

Well, it does more than that (as you can see by the IRQ assignments), but essentially it doesn't make much difference (unless it causes problems!).

 

[MikeyWeitz]

you will get the, "It's now safe to shut down your computer crap as well as it wont auto power off!

 

[Rob Gillespie]

you will get the, "It's now safe to shut down your computer crap as well as it wont auto power off!

That can be sorted out easily enough. In Device Manager, make sure the Show Hidden Devices option is enabled, then enable the NT Apm/Legacy Interface Node device under NT/Apm Legacy Support.

 

[Max Leung]

Turning off ACPI could make things worse! Be really careful if you do this.

Usually laptops and cheap-ass motherboards will assign everything device on IRQs 9 and 11, regardless of OS. Really annoying, but there is almost nothing you can do about it.

I suggest ghosting your hard drive before you proceed. Or, just reinstall once more if it doesn't help on your first attempt.

Anyhow, USB controllers really dislike having any other devices sharing the same IRQ.

Maybe you can go into the BIOS, and disable any unused COM ports or parallel ports, to see if the OS will remap some of the devices away from IRQ 9.

Good luck!

 

[Scott L]

Just an update, I removed all my PCI cards except the capture card which was having mucho trouble before. After booting the system it worked perfectly! So whether XP is designed to handle multiple IRQs or not, this capture card will only work if it's the only PCI card in the machine. Isn't that veeeeird???
I'm in the process of upgrading to a P4 based system with a new Asus mobo. If the card still doesn't like to work with its PCI buddies it's going back.
btw- this is the Pixelview Xcapture card that is only $39. It has been getting good reviews on AVS, but only from the people who can get it to work!

 

[Max Leung]

The OS isn't a prime factor with how well a device shares an IRQ. It all depends on the quality of the drivers that ship with the card, as well as the hardware design of the card itself.
As a driver writer myself, I can attest to this. Too many people blame Windows XP or Windows 98, etc. when quite simply it's the manufacturer of the card that is to blame!
Don't blame the OS! Blame the damn manufacturer! Grrr.
What motherboard are you gonna get? Too bad you're not getting an AMD...the nForce1/2 motherboards kick ass!
I have to admit, Intel is stomping AMD right now...I wish nvidia would make P4 chipsets. :frowning:

 

[Mike Veroukis]

Well, I would first recommend freeing up as many IRQs as possible. Some motherboards have built modems that are usually not used if you're using high-speed internet. You can disable these on board modems either via a jumper on the motherboard or via the BIOS.

Also, if you are not using the COM ports or the parallel port, you can usually disable those in the BIOS as well. Even USB ports can be disabled. Basically, I disable anything that's not being used, there's no need to tie up an IRQ and no need to load an un-used driver.

- Mike

 

[Kimmo Jaskari]

Usually you can get a free irq for all the internal devices if you try.

Switching ACPI off on an existing installtion can indeed cause trouble, so the best way to do it is a clean reinstall of the operating system and disabling ACPI on install.

On even slightly modern motherboards there are settings for IRQs and the PCI card that you can change in the BIOS, usually accessible by hitting DEL before the machine boots. Care is required while in the BIOS settings though, you can foul stuff up if you are too careless.

On my most recent reinstall I just entered that BIOS setup program and with a few adjustments I had no problems assigning all my internal devices dedicated IRQ's. I could even specify which PCI slot (and thus which card) would get which IRQ.

The machine is working better than it ever has before.

 

[Darren Lewis]

If you're interested, there's a good article about ACPI here. It's related to pro-audio computers running high end stuff like Cubase and Nuendo, but it's probably relevent to capture cards too.
Another article briefly covering ACPI and APIC motherboards is here
Having said that, we've got a pro-audio PC running Cubase SX on Windows XP Pro with ACPI and not had any problems. The audio card isn't sharing any IRQs though.
Sometimes moving cards to other PCI slots will make them use different IRQs.