I managed to install the SMP kernel and ACPI (see thread
How to deinstal ACPI driver?)
https://www.os2world.com/forum/index.php/topic,1759.0.html.
But now the CPU fan makes much more noise than before. It seems that the halt functionality (Pulse CPU load 0,0%) works fine, but if the CPU load increases over 0,0%, the processor energy consumption goes to maximum when pulse shows values only little higher than 0,0%.
There is a file c:\mptn\etc\acpid.cfg.sample which I have copied to c:\acpid.cfg and I have added this filename behind RUN=C:\OS2\ACPIDAEMON.EXE in the config.sys.
There are different settings described in the file c:\sys\doc\acpi\psd_en.inf, page "Power Manager Settings".
I have tried these settings:
; MinPower is the minimum power level for energy saving (13 - 100), default=25
MinPower = 13
; IncIfAbove is the CPU load above which CPU power is increased (1-100), default=25
IncIfAbove = 75
; DecIfBelow is the CPU load below which CPU power is decreased (1-100), default=15
DecIfBelow = 65
But this makes no remarkable effect. I assume that my problem ist that the CPU can only distinguish between HALT and Maximum. Any ideas?