There's a trick if you're willing to redo the Windows XP install.
When still in text mode setup, when it asks to press F6 for extra drivers, hit F7. It will allow you to select the PC type.
Change from 'ACPI compliant' to 'Standard Computer' and it will install XP with no ACPI support.
Other option, if you can boot in safe mode, is to manually change the HAL from ACPI to non-ACPI.
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In Device Manager, right-click on "Advanced Configuration and Power Interface (ACPI) PC" under the "Computer" header and select "Update Driver".
Select "Install from a list or specific location (advanced)" and click Next.
Select "Don't Search. I will choose the driver to install" and click Next.
Select "Standard PC" and click Next.
Click Next and OK to the end.
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