http://hardforum.com/showthread.php?t=1521388
Bios changes, after 'Load Performance Defaults'
Advanced -> Power Configuration ACPI Version Features [ACPI v2.0] Energy Lake Feature [Enabled] APIC ACPI SCI IRQ [Enabled] High Performance Event Timer [Enabled] Restore on AC Power Loss by IO [Last State] Chipset -> North Bridge Chipset Configuration Internal Graphics Mode Select [Enabled, 1MB]
Setting ACPI version to 3.0 screws up thermal reporting (and probably reaction) on FreeBSD 8.1/amd64.