Re: [opensuse-kernel] kernel & BIOS report (incorrectly?)=?iso-8859-1?q?=09=09_differentcurrent/available_speeds_for_overclocked?= CPU

Le lundi 03 août 2009, Jeff Mahoney a écrit :

Jan Beulich wrote:

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Jeff Mahoney 03.08.09 16:33 >>> The thing is that the non-CnQ mode is reported as 3.7 GHz. I don't know enough about CnQ to know why that is - but values outside of the original tables are getting reported if we're seeing the 3.7 GHz there.

What "original tables" are you referring to? The 3.7 GHz is a measured value, not one read from any tables. All the frequencies the powernow driver reports are table derived (and hence susceptible to BIOS issues).

The ACPI tables you mentioned in your previous post. Maybe I misunderstood.

It's quite some time since I last played with cpufreq, but I think it can be explained that way: * Asus' Cool'n'Quiet is essentially AMD's PowerNow! rebranded. That is, an implementation of cpufreq. * When cpufreq is not used, the frequency reported in /proc/cpuinfo is the one measured at boot time. * When cpufreq is used, the frequency measured at boot time is no longer relevant as we _know_ it will change over time. So the frequency reported in /proc/cpuinfo is provided by the cpufreq driver and changes dynamically. It's relatively easy to differentiate between these cases by just looking at the frequency value. Measured ones have varying digits, while cpufreq-provided ones always end with zeroes: cpu MHz : 1996.939 versus cpu MHz : 1000.000 So basically, incorrect frequency tables from the BIOS have no effect when cpufreq/CnQ/PowerNow is not used. And my conclusion is the same as Jan's: the vendor offers overclocking capabilities as a selling argument, but did not actually design its BIOS to handle it properly. -- Jean Delvare Suse L3 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-kernel+help@opensuse.org