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I have an acer aspire 7560 that on windows supported (through acer proprietary software) boosting the cpu from 1.9ghz to up to 2.5ghz for long periods of time so long as there was adequate cooling. On ubuntu, I get a top speed of 1.9ghz no matter what I do. I am not trying to overclock past what it is supposed to go, but basically how would I go about doing this? I have googled everywhere and everyone recommends using the bios and that if there isn't an option there it can't be done. I know it can, I know it can be done and still be stable on this computer, and I know that it is possible to do through simple software. My processor is an AMD Fusion A8-3520M quad-core 64 bit processor with integrated radeon graphics and 4gb of ram. Thanks in advance.

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  • you overclock the processor in BIOS. and it's not always that easy. This is most likely off topic since it's not really about Ubuntu... – Alvar Jul 24 '14 at 21:00
  • I have to use ubuntu, when it was running windows it would automatically boost it. there is NO OPTION in the bios to change it, it just did it automatically – sbergeron Jul 24 '14 at 21:01
  • and it is about ubuntu as I am trying to figure out how to overclock with ubuntu. Sorry I have to ask, but did you read the question fully? – sbergeron Jul 24 '14 at 21:01
  • did you read my comment fully? jupiter supports processor down clock (on some cpu). You can try that, search the site for it. But it's not simple software to overclock the processor. it's normally done in the BIOS, but then it's only a stable overclock, like alwyas running at 2.3 GHZ. if you want boost then you need to have unlocked multiple (mine is at 34 (34*100 mhz = 3.4ghz ish.) but that's rare on laptops. – Alvar Jul 24 '14 at 21:05
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    I was just pointed at this website yesterday (kernel.org/doc/Documentation/cpu-freq/boost.txt) which discusses boost and AMD. – Charles Green Jul 24 '14 at 21:15
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[Update 2015]

Starting with Linux 3.16:

  • The value for bapm can be provided as a module parameter (see here).

  • The value of bapm is set to 1 by default for Kaveri, Kabini and desktop Trinity, Richland systems (see here), resulting in Turbo Core being enabled.

Which means that with Kernel 3.16 or later, Turbo Core should work right out of the box with radeon in many cases.

If you run Debian, or if you run Ubuntu and the above is not true for you, please refer to How to set up a Debian system (focus on 2D or console/server) with an AMD Turbo Core APU for maximum energy and computing efficiency?

[Update 2014-Aug-07]

I published a detailed analysis over at unix-stackexchange.com which contains (at least for me) a few surprises. Such as the ondemand governor potentially being worse than performance (at least with the Richland A10-6700) and fglrx apparently using some questionable tricks to improve short-term boosts, abruptly having to compensate for that in the long run. I'm glad I had a closer look at this.

[Original Answer]

AMD Turbo Core is supposed to be enabled by default in all current Linux versions.

Turbo Core, however, is a feature available on AMD CPUs with and without integrated GPU. And there seem to be two issues regarding those with an integrated GPU. Your A8 falls into this category.

  • If the kernel does not have the ATI/AMD 'fglrx' module loaded, the APUs appear to stick to the non-boost/regular frequencies. I presume that the reason is that Turbo Core is a decision made by the APU itself, based on several criteria such as power dissipation/TDP. It seems that the GPU on the chip will not contribute to the decision unless it gets initialised properly. And properly here means that you must use the official dirver; not even the free radeonwill do the trick. I have filed a bug report over at kernel.org but the question remains whether it will be easy to have the kernel initialise the GPU just for the sake of the boost (if my assumption about the root cause is correct).
  • However, even with fglrx, there appears to be a bug if you intend to use Dynamic Power Management.

For a bit more of explanation e.g. about which tools correctly identify boosts, see here.

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  • All of that is nice and dandy, but OP has Llano. Bidirectional APM didn't exist there. Perhaps the GPU could still influence the CPU headroom (pm only came in 3.13) but maybe he was just running 12.04 LTS (no version was mentioned) and missing out the 2012 cpufreq rework. Or nothing is wrong already. – mirh Dec 3 '20 at 17:16

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