AMD Black Edition and cpufreq

[piteq]

Hello;

I can't find any information regarding the possibility to change the CPU frequency multiplier in CPUs that have their multipliers unlocked (like said Black Edition AMD CPUs). The only way I can achieve the expected speed is based on disabling the Cool'n'Quiet function and force the multiplier in BIOS CPU settings. At the moment the cpufreq correctly recognizes my CPU (Black Edition 5000+) and runs it at 2.6 GHz max (it's out of the box speed of this CPU), but I can't do anything to make it work similarly to Windows (15x 200MHz).

I'm complete newb to Linux and I'm currently trying to make a switch from Windows; managed to fix some things using available information, but this one puzzles me

br,
p.

[majikthise]

2.6 GHz is the stock Frequency for a bog-standard 5000+

You have to adjust the BIOS parameters to overclock (maybe underclock if you wanted a quiet pc) Google around for a guide to getting the most out of your unlocked cpu.

[piteq]

Originally Posted by majikthise

2.6 GHz is the stock Frequency for a bog-standard 5000+

You have to adjust the BIOS parameters to overclock (maybe underclock if you wanted a quiet pc) Google around for a guide to getting the most out of your unlocked cpu.

Aye, I know its stock speed is 2.6GHz But under Windows I can define own FID/VID pairs, overriding the hardware limits reported by BIOS, using programs like RMClock. So I can easily overclock it to 3GHz on the fly, using such software.

In other words, I'm looking for possibility to do the same under Linux, but cpufreq allows me only to change speed of the CPU within the hardware limits. When I try to set speed higher than the 2.60 it's set to 2.60. I also can't edit files like /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq where the max frequency of the CPU is stored (access denied).

Will try to look further

[bowens44]

I am thinking of buying this processor with the intent of overclocking it to 3 GHz so I want to be sure I understand what yu are saying. Are you saying tha if you overclock the cpu via the BIOS . linux doesn't recognize the processor speed as 3 GHz ?

[majikthise]

Dynamic CPU overclocking via Windoze, that's the nuttiest thing I've heard in ages.
IMO a one-way ticket to a hosed system

Does the windows overclocking utility allow voltage changes simultaneously?

[majikthise]

The way I read it on the RMClock website. You Overclock in the BIOS first and then use RMClock to throttle the frequency down.

In short, it's an advanced Cool 'n' Quiet.

[piteq]

Originally Posted by bowens44

I am thinking of buying this processor with the intent of overclocking it to 3 GHz so I want to be sure I understand what yu are saying. Are you saying tha if you overclock the cpu via the BIOS . linux doesn't recognize the processor speed as 3 GHz ?

Nono; if you set the CPU speed via BIOS AND disable C'n'Q feature, it is recognized properly as 3GHz part (according to cpufreq-info). But since the C'n'Q is disabled, the CPU works always at 3GHz no matter if the additional horsepower is needed or not. Since I mostly write and edit stuff, and only sometimes play games, I need that power only sometimes. That's why it bothers me ;-) If you set the CPU speed via BIOS, but DON'T disable C'n'Q, then it's recognized as 2.6GHz, no matter what you were trying to force. Maybe it's also BIOS issue (I got ASUS M2N-SLI Deluxe).

@majikthise: Aye, RMClock allows to set any voltage (VID) - provided motherboard can deliver it - and multiplier (FID). Also, it allows to define any number of intermediate "states" (so depending on the CPU load it can be automatically clocked at let's say 1GHz and supplied with 1.125V, 2GHz and 1.325V, 3GHz and 1.4V, and so on). It's not needed to set the maximum multiplier in BIOS for it to work; only the C'n'Q must be enabled (and CPU drivers installed in OS, of course; they need to support throttling). I'm using it almost 5 months now and it's working perfectly, just needed to configure it a bit at the beginning. So, it's theoretically similar to cpufreq-set (and the rest of utils) - from functional point of view the only difference is that cpufreq doesn't allow me to override default max CPU speed, while RMClock does. And that's what I'm trying to change

[majikthise]

Originally Posted by piteq

That's why it bothers me ;-) If you set the CPU speed via BIOS, but DON'T disable C'n'Q, then it's recognized as 2.6GHz,

But that's probably a 'step' in the freq-scaling ladder. Do you agree? It depends on the multiples the memory speed, doesn't it? ie 3GHz minus 2.6GHz = 400 and that's possibly the smallest step size in when stepping down/up.

try this forum:
http://www.atomicmpc.com.au/forums.a...c=6&t=8472&p=0