Intel Speedstep work in Ubuntu, but un-does my overclock

[timzak]

I enabled Speedstep in my motherboard bios and was happy to see it supported in Ubuntu. However, when I enable Speedstep, I lose my cpu overclock. I have an E4300 running at 2.4Ghz. It runs @ 2.4 with Speedstep disabled, but when I enable it my cpu runs @ 1.2 Ghz throttled, and 1.8 Ghz (my cpu's stock speed) when usage goes up to 100%.

I am using conky to measure cpu speed in Ubuntu. I am using a gnome panel applet to measure cpu throttling (I forget what it's called at the moment). Basically, when the cpu is idle, it runs at 66% speed, which conky reports as 1.2 Ghz. When it ramps up to 100% speed, conky reports 1.8 Ghz.

If I go into my bios and turn Speedstep back off, then boot back into Ubuntu, conky again reports my cpu speed @ 2.4 Ghz.

So is this a motherboard issue or a Linux issue? Can anyone test this on their system?

Thanks.

 

[DaiShan]

Speedstep is designed to save power and reduce heat output. Hence it is working as intended in your system. If you want to OC, you need to disable Speedstep, if you want better battery life, then turn it back on.

 

[dandragonrage]

What? No. Speedstep works fine with overclocking on my setup in Windows. 3.2GHz normal, 2.4GHz with EIST enabled instead of 2.4 and 1.6 respectively. Unfortunately, I'm not sure how Linux/your motherboard might handle this differently.

 

[timzak]

Yeah, I'm sure I've seen reports of people overclocking their systems and Speedstep throttling their cpu speed down from their overclocked speed. In my case, it's ignoring my overclock and throttling the speed down from its stock speed. This is why I'm posting here...hoping someone can tell me if this is a Linux-specific issue with their kernel, or if it's my motherboard.

Thanks.

 

[Alone]

That's what Speedstep does.

 

[Nothinman]

It's probably something ACPI related but I would have no clue even where to start besides emailing lkml or filing a bug report on bugzilla.kernel.org and seeing if any of the kernel devs will help.

 

[xtknight]

AFAIK you need to use the userspace governor to control the CPU frequency. Here's a good guide: http://rffr.de/acpi

 

[timzak]

Originally posted by: xtknight
AFAIK you need to use the userspace governor to control the CPU frequency. Here's a good guide: http://rffr.de/acpi

Thank you very much for the link. That looks promising! I'll check into it this evening.