Win2K, ACPI, and IRQ Sharing is a good thing?

[Cnemie]

Hello,

I have been reading the numerous posts on the ACPI/IRQ Sharing topic and I have found that, on my Win2k set up, ACPI/IRQ sharing is not a good thing.

I have an Intel 815EEA MB and P3 800EB processor with a host of PCI cards and peripherals. On my old tried and true set up.......... 3 processors/2 MBS (including both AMD and Intel offerings)and every driver installed at least once......my set up uses the full spectrum of IRQs and very few share the same one.

On my new hard drive, and a fresh install, Win2K decided to slam everything on the same IRQ--number 9. The result is a noticable system degradation and a quantifiable frame rate drop in games. I have 8 devices sharing IRQ 9.

This is frustrating because the old hackneyed set up works like a dream and the new fresh set up works like crap. What I fail to understand is why, on the same exact set up, did Win2K decide to do things differently? The only difference between the two set ups is the hard drive and the day of the week, and yet the new set up results in very different results.

Finally, what is the easiest way to isolate the video card from the shared devices? If I could just get my GeForce card to use its own IRQ, I could live with the set up.

Thanks.

 

[AndyHui]

Normally ACPI is a good thing as long as all of your devices are FULLY compliant and do not have a problem with sharing IRQs. Unfortunately, unless you have the very latest hardware, chances are that you may run into problems.

Normally I recommend that you leave the system on ACPI if you are having no problems.

Anyway, here is the article from Microsoft dealing with it.

If you want to manually assign IRQs, or just let Windows do it properly, you have to change the ACPI mode HAL to Standard PC HAL.

To do this, go into Device Manager, and look under Computer. It should say Advanced Configuration Power Interface PC. Change this to Standard PC by changing the driver. Then reboot. Hopefully it should come out OK.

You may lose the ability for Win2K to shut down properly by itself. If this is the case, you will need to disable the ACPI driver and install the APM driver. I recommend doing a reinstall for full system support.

If you need to reinstall, hit F5 while it is detecting all the devices right at the very beginning to manually select the Standard PC HAL. You may also need to turn ACPI off in the BIOS if you have that option.