IRQ sharing too much in Win 2k/XP

[Arkaine23]

I noticed when I installed a new USB controller card, that my USB, onboard audio, video card, and and Nic were all sharing IRQ11. With just the Nic, sound, and video sharing the IRQ, I had pretty good 3dmark scores for my system and vid card. But after installing the USB controller my scores dropped by 1200 points!!! Then I tried to manually change my IRQ settings, and found them locked! I switched slots on my PCI devices, and they still all used IRQ 11!

SO I was looking around for a fix, and I noticed that this problem is fairly common for Win 2000/XP users.

So far I've found two possible fixes:

1) Reserve the overly-shared IRQ in bios and see if that redistributes the IRQ resources.

2) Change bios and disable ACPI. Then format and clean-install OS.

I haven't tried either of these yet, but I will tonight after work. Hope this works for those of us with this sorta resource sharing trouble.

[redduc900]

I've found that W2K and XP both seem to ignore the reserving of IRQ's in the BIOS, whether ACPI is enabled or disabled. With my setup and ACPI enabled, everything seems to revolve around IRQ11 (four differrent devices sharing the same IRQ, including my video card). The only way that I've found around this dilemma, is by using a modded BIOS which allows the disabling of ACPI...and leaving all the IRQ settings in the BIOS set to Auto.

From what I understand, ACPI can also be disabled using this method (although I haven't tried it yet)...

When doing a clean install, you'll be asked to press F6 if you have any SCSI drivers to install (at the "Setup is inspecting your computer's hardware configuration" screen)..press F7 immediately after seeing this screen, to load the "Standard PC" HAL (disable ACPI). Another way of doing this is to press F5 instead of F7 (at least in W2K, I'm not sure if this will work in XP), which will present you with the following options...

Click the appropriate HAL (Hardware Abstraction Layer), or click "Other" to specify a third-party HAL. The available HAL's include:

ACPI Multiprocessor PC
ACPI Uniprocessor PC
Advanced Configuration and Power Interface (ACPI) PC
Compaq SystemPro Multiprocessor or 100% Compatible
MPS Uniprocessor PC
MPS Multiprocessor PC
Standard PC
Standard PC with C-Step i486
Other;)

[Arkaine23]

1st, IRQ 5 and 7 are free on my computer right now. Win 2k pro SP2.

I'm going to try reserving irq 11 first, and then I'll try disabling ACPI and re-installing...

Will disabling ACPI unlock the manual resource settings in the device manager? I'd really like to be able to adjust this stuff through windows.

Do you think disabling the PlugnPlay OS installed setting in my bios will help with the irq distribution?

If I clean install, should I remove my Nic and USB card and put them in after I get everything else set up? Or leave them in during the install?

[Arkaine23]

Device manager---> +Computer---> ACPI---> properties---> update driver ---> choose: standard PC.

Disables ACPI and redistributes devices. Requires at least one reboot and probably some devices need a re-install. Look for APM tab in power managenment and check it to keep automatic shutdown. No big loss really though.

Each device should then have its own IRQ or maybe just two devices sharing one IRQ.

Is it safe to disable PS/2 ports IRQ if you use USB for keyboard & mouse? Will that free up those IRQ's? Com ports? Serial ports?

[ken257]

I have been through this same situation with way to much sharing. The best solution for me was the same as someone stated above. I used a bios editing program to enable the option to disable ACPI. Flashed the new bios and reinstalled windows, now I have no sharing :)

The option to enable/dissable ACPI is acctualy in your bios already but it is just hidden from use. Seems good old Microsoft has there hand in this because they require ACPI to be permanently enabled to meet there hardware certification! LAME!!!

[Arkaine23]

I also just hooked up a Linksys 4 port router w/ firewall. Could that have caused my 3dmark score to drop?

1 more hour of work and then I can get back to restoring my previous 3dmark scores!

[Arkaine23]

previous score restored. Had to format/reinstall.