# Overclocked Core 2 Duo (E2xxx) and freq scaling

## adrin

Will frequency scaling work on an overclocked Pentium Dual Core (C2D) CPU?

It seems that scaling works when the cpu isnt OCed, and after i overclock it cpufreqd does not detect my CPU (unknown cpu or similar error)

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## your_WooDness

Hi,

same on my Athlon X2. When it's overclocked the cpu-freq doesn't work. I think that the cpu-freq is getting the information which states are possible directly from a table in the CPU. When the CPU is overclocked the values in the table doesn't fit the values of GHz your CPU is actually running and so the cpu-freq doesn't recognizes the states.

Don't know if this is correct, but it seems logical to me.

WooD

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## adrin

hmm yes i think you are right, it just cannot find correct scaling range or something, is there a way to override it? I think windows deals with freq scaling on OCed CPU quite well.

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## __jata__

Hi,

same here on E8400: normally it runs at 3.00 GHz and everything is ok. Any attempt to overclock or underclock the processor means automatically impossibility to use any governor (/sys/devices/system/cpu/0,1/cpufreq directories diseappear). Pitty, because this processor is rock stable at 3.30 GHz.

Even worse, I have Q6600 in my other PC (MB Asus P5WDG2 WS Pro) and I cannot find the appropriate settings for the nominal frequency ('default' freq means 2404 MHz instead 2400 MHz, it seems Asus does some kind a slight overclocking by default), and therefore any frequency modification is unavailable at all (under linux).

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## gentoo_ram

I have gotten some cpu-freq stuff working on my overclocked E8400.  But from what I can tell, it only supports using a 6.0 clock/bus multiplier (low power) and 9.0 clock/bus multiplier (full speed) on my motherboard (ASUS P5N32-E SLI) with the latest BIOS.  Under normal clocking, that's 2.0GHz and 3.0 GHz only.  When I overclocked, it was 2.4 and 3.6 GHZ.  It works under both Windows and Linux.  It's a joke compared to my AMD64 machine which offers a variety of frequencies that really save power.  I just leave it disabled on my Intel box since it's so useless.

By comparison, my AMD box does:

```

Freq         Ticks

1.00     155310397 ( 99.2%)

1.80        460840 (  0.3%)

2.00         47006 (  0.0%)

2.20         29394 (  0.0%)

2.40         30871 (  0.0%)

2.60         21943 (  0.0%)

2.80         20605 (  0.0%)

3.00        661526 (  0.4%)

```

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## shredder

Gentoo_ram's mobo is from ASUS, but you others may have a Gigabyte. http://www.phoronix.com/forums/showthread.php?p=34150

Possible that applying BIOS updates for ASUS mobos solves the problem too.

Maybe it is possible to manipulate cpufreq settings under: /sys/devices/system/cpu/cpu*/cpufreq/

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## adrin

well i have a gigabyte board, I will upgrade to the latest bios and see if anything improves...

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