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DSDT SpeedStep on acer 5135

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I'm using linux on a old Arcer Aspire 5315. I replaced sometime ago the original CPU by a T8100

I know that this forum not is focused on linux, but is the best resource that I know about DSDT modifications.

This is my current DSDT

The computer works fine but the are some issues that maybe I can fix with a proper DSDT

The CPU is working at 2 Ghz but should be 2.1 Ghz

It's a BIOS limitation that I need to fix

root@antiX1:/home/Carlos/Bios# cat /sys/devices/system/cpu/cpu0/cpufreq/bios_limit

I found this during boot

[ 2.218733] [Firmware Bug]: ACPI: Invalid BIOS _PSS frequency found for processor 0: 0x0 MHz

[ 2.218904] [Firmware Bug]: ACPI: Invalid BIOS _PSS frequency found for processor 1: 0x0 MHz

I suppose that is due my DSDT


Scope (_PR)
       Processor (CPU0, 0x01, 0x00000410, 0x06) {}
       Processor (CPU1, 0x02, 0x00000410, 0x06) {}


In a correct system the CPU should work from 800 MHz to 2.10 GHz

I'm confused about how populate that section... looks like I need to put the values for my current CPU (T8100) but...

-BIOS is supposed to works with a full range of CPUs, why I need to put my current one a not something valid for a entire family of CPUs?

In any case... i have found come calculators to generate the section but all are for Mac SO.

There is some SpeedStep calculator that works on windows/Linux? if not... how can I calculate the correct values?

Edited by Guest
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in mac os x is the boot loader .. will go generate the states..

in linux no clue..

if it have same behavior in windows .. maybe something is wrong with ur bios

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u have a c2d ..

that patch is not for ur cpu ..

if u extract ssdt tables maybe u see what is wrong with ur speed step



I have check my SSTD and I think that modify that is not possible with my current knowledge

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