ACPI vs. MPS Multiprocessor PC

[Jonitus]

I had been noticing alot of entries in my error logs (Windows XP Pro) when it came to ACPI, such as:

ACPI BIOS has attempted to write to a protected memory area

To resolve this, I updated the driver for ACPI to MPS...and the errors are no more....WHY?

 

[AndyHui]

MPS = APM for multiprocessor systems.

Essentially this is the same HAL as the Standard APM HAL, but with SMP support.

Your ACPI BIOS errors are due to your BIOS not being fully ACPI compliant. If possible, you should upgrade your BIOS to the latest version.

 

[Jonitus]

Assuming I can find a BIOS update, flash my BIOS, and everything with that works OK, how can I cange back to ACPI? Upon lookin now, I don't see the option for switching the driver.

I like ACPI...hell, I'm lazy and don't want to manually power off my system.


Also, why is my performance now soooooo much better than before? Programs open faster, etc.

 

[AndyHui]

Go look at my Why are all my devices using one IRQ in Win2K/WinXP FAQ for how to change the HAL properly.

You are losing a lot more than just the ability to software shutdown. The APM dual processor HAL also does not have the ability to address more than 16 IRQs that an SMP system provides. Most basic x86 SMP systems provide anywhere between 24 and 32 hardware IRQs.

You have much faster performance because you have real problems when the ACPI HAL talks to a non-ACPI compliant BIOS.