Fan control software: list of supported laptops

The range of systems the tool support is comprehensive, but not extensive or universal. This tool is created by “Grantig” a user on the computer base forums, and it supports many modern notebooks. The EC's firmware uses the PECI bus to read the DTSs of the CPU and adjust fan speeds accordingly at known register offsets in its MMIO space.Download Notebook Fan Control NOTEBOOK FAN CONTROL 1.6.3 Some LDNs expose IO base address registers in their own space (offset 30h–FFh) which allow extra registers to be mapped in. All of the PWM and PECI registers are no longer logical devices and their registers are only mapped into the MMIO space of the on board EC CPU, leaving only a few generic registers in the regular IO space visible to the host. With the ECs, the registers have been separated into host view and an EC view.

A bit in the LPC bridge on the PCH is used to select whether to expose ports 2F/2E or 4F/4E. This would cause the configuration space of the LDN at offset 30h–FFh to be mapped in at the ports, which can then be accessed using the index and then read/writing to the data register. You used to be able to select a SuperIO logical device by writing 07h to I/O port 2Eh (Index register) which cause the southbridge to generate LPC cycles which cause the SIO to select the LDN register (at offset 07h in the generic space: offsets 00h–30h) and then write the LDN to port 2Fh (data register) to generate LPC cycles that cause the SIO to select that LDN. The EC's PWM HW is accessible only from the EC, the OS has no longer control over the CPU FAN if not by setting the CPU throttling policy. ECs have their firmware and use the PECI interface to read the DTS of the CPU. It's worth noting that 9y later the SuperIOs are gone in laptop systems, replaced by the ECs. Programmatically, you'd need to create a kernel mode driver that uses MmMapIoSpace and handles IOCTLs off the IRP_MJ_CONTROL major function and then call StartServiceManager, CreateService and StartService on it and then send IOCTLs using DeviceIoControl to perform tasks which manipulate underlying physical memory / IO space / MSRs.

Control fan laptop