7 Important Technology Information

7.5.5Processor Clock Throttling

The ACPI OS assesses the optimum CPU performance change necessary to lower the temperature using the following equation:

ΔP[%] = TC1(Tn-Tn-1) + TC2(Tn-Tt)

ΔP is the performance delta, Tt is the target temperature = passive cooling trip point. The two coefficients TC1 and TC2 and the sampling period TSP are hardware dependent constants the end user must supply (setup options section ACPI Control Submenu).

It’s up to the end user to set the cooling preference of the system by setting the appropriate trip points in the BIOS setup.

Note:

See chapter 12 of the ACPI specification (www.acpi.info) for more details.

 

 

7.6ACPI Suspend Modes and Resume Events

The ETX®-CD, supports the S1 (POS=Power On Suspend) state, S3 and S4.

S4 (=Save to Disk) is not supported by the BIOS (S4_BIOS) but it is supported by the following operating systems:

WinME

Win2k

WinXP (S4_OS=Hibernate)

The following events resume the system from S1:

Power Button

PS/2 Keyboard and Mouse IRQs (1 & 12) USB Wake Events

PCI Bus signal PME#

Kontron User's Guide ETX CD

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Intel ETX CD manual Acpi Suspend Modes and Resume Events, Processor Clock Throttling