CPU speed and Turbo Boost.

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Hey everyone! I got a question to ask: Are there any connections between Turbo Boost and CPU speed? I was wondering why the computer had turbo boost when my CPU speed is like 42%? :)
 
Solution

What do you mean by "CPU speed is like 42%"? Do you mean CPU usage?

Turbo Boost basically works like this: Normally, the CPU runs in a low-power idle mode when you're doing such things as surfing the web or using a word processing program. Any time the CPU senses that one or more of its cores are under load, it automatically ramps up the CPU speed. The final Turbo Boost speed depends on how many cores are loaded.

Example: Say you have one of the new Sandy Bridge i5-2500 processors (quad core, default clock speed 3.3GHz). Sitting at the Windows...
What is Intel® Turbo Boost? This technology looks at how the processor is running, where it is using all the cores and it TDP (Thermal Design Power) if it hasn’t reached these limits it will increase the clock speed up to reach a faster speed to stay within the TDP. You can install this software and it will show you when your processor clocks up speed in Intel Turbo Boost http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&DwnldID=19105. Most of the time your system won’t be using Intel Turbo Boost but when you need increased performance it is nice to have it right there waiting for you to use. For more information on the Intel Turbo Boost Technology you can check this out http://www.intel.com/support/processors/sb/CS-029908.htm?wapkw=(turbo+boost).

Christian Wood
Intel Enthusiast Team
 

Are you working directly from Intel or an intel expert at Tomshardware?
 


I do have the software in my computer, and most of the time it has the blue bar rising. Does it represent 1 core or both cores "dynamic overclocking"?
 

What do you mean by "CPU speed is like 42%"? Do you mean CPU usage?

Turbo Boost basically works like this: Normally, the CPU runs in a low-power idle mode when you're doing such things as surfing the web or using a word processing program. Any time the CPU senses that one or more of its cores are under load, it automatically ramps up the CPU speed. The final Turbo Boost speed depends on how many cores are loaded.

Example: Say you have one of the new Sandy Bridge i5-2500 processors (quad core, default clock speed 3.3GHz). Sitting at the Windows desktop, it runs at 1.6GHz (the low-power idle mode). If you start up Mass Effect 2 or StarCraft II or any other demanding game (or a program like Prime95), Turbo Boost goes to work ramping up the speed. With four cores loaded it goes to 3.4GHz, with three loaded it goes to 3.5GHz, with two loaded it goes to 3.6GHz, and with only one loaded it goes to 3.7GHz. As soon as you exit the game or program, it goes back down to 1.6GHz.
 
Solution


I work for Intel® on the Enthusiast team. This is a fairly new effort by Intel to reach out to the enthusiast, DIY'er, power user space in a social media context (in other words on boards like this one).

The blue bar on Intel Turbo Boost Monitor only shows the clock speed of the processor not the number of core or threads in use. The bottom is the normal clock speed while it can clock up to a higher rate based on TDP and need. Understand that if you aren't doing much the processor is going to be running at a very low level to save power.

Christian Wood
Intel Enthusiast Team
 
@intelenthusiast

maybe you can answer this. if the max safe thermal limit on the mobile sb i7's is 100* c why do the downclock at 80*c ish or there about? i was told by the manufacture that the critical temp was 130 and safe was 100. so why downclock at 80?
 


In cases like this most likely the OEM (Dell, HP, etc.) will set the temperature low to help extend the life (battery, or other components within the laptop) based on their testing. They may have found that there is a problem with airflow or some other issue when they reach 100˚c or the battery life may be greatly lowered this is generally a big selling point so they want to give as big of a battery life as possible. I don’t know the exact answer for the OEM that you are talking about but that would be my guess.
 



samsung rf511? its a i7 2630qm. is there anything that i can do?
 


Hmm, OK so you're sorta like JF-AMD (AMD's director of server marketing) who frequently posts here, and manages to divulge zero AMD secrets to us eager fans either 😛..

So, what exactly was Paul Otellini referring to when he said Intel's 22nm would be "revolutionary"?? 😀
 


Hmm, I got a related question. I have a stock cooled i7 870 and I recently flashed my bios and now turbo boost kicks in even if the CPU is at full load. I run BOINC on it so unless I'm gaming the CPU will be at full load. The boosting causes the temps to spike up to almost 100 degrees celsius for each core. I was a bit alarmed by this so I've turned turbo boost off for now. I'm definitely planning to replace the stock cooler though, especially with summer just around the corner.

My question basically is if it's safe to let it use turbo boost since you said it'll boost unless it exceeds the TDP, or could I perhaps configure turbo boost somehow to only use it when CPU usage is lower? It's quite nice to have while gaming since most games don't really use many threads yet.

edit
I also got hyperthreading enabled, this doesn't help keep the temps down of course.
 
I just built an i7 870 system on an Intel DP55KG motherboard. The Turbo Boost doesn't work at all and I'm running the latest BIOS update (July 2011) and everything is enabled and in "automatic" mode. I've tried several CPU "stress" type application (Intel Burn, Prime95, etc) and NEVER see my CPU speed go beyond 2.93ghz. I've used different CPU monitoring apps, too, and there was no difference. Any thoughts? I'm running a Coolermaster Hyper 212+ with dual fans for the CPU cooler, so my temps are fine. As I understand it, I should be seeing 3.6ghz when one core is utilized and 3.2ghz across the board with all four cores utilized.
 

So if I were going to oc to 4.0 is it better to turn turbo boost off and have it run at 4.0 ghz all the time? Or have it run at a low frequency idle and when I play games have it run @ 4.0-4.4?
 


How do I disable turbo if its not an option in my Bios? I bought a used i7 Desktop and it has been over clocked w/turbo. It runs hot and I don't know how to get it back to default settings. It has a Bios that is all but worthless.
 

If the BIOS doesn't have overclocking or Turbo settings, the only way the computer can be overclocked is through software in Windows. Uninstall any and all overclocking software and that should disable the overclock. Turbo should be left on.

Otherwise, every BIOS has a "reset to defaults" or similar option. You could do that, just in case the overclocking options are hidden.