CPU overclocked on it's own?

[kitekrazy]

My 9900K is running at 4.6ghz.   I did nothing in the bios or use any other software utility to increase this speed.   A ghost in the machine? This is the first k series Intel I've had.

[Tony Carpenter]

@kitekrazy That will be turbo mode. Unless the bios is told though I believe it can throttle down under certain circumstances. It is possible if you have a good setup to disable throttling on some motherboards. Mine has such a feature it was naturally doing 4.1ghz, it's a 10940x 14 core, that was quick. I ran the Intel program that does a number of things including testing a LOT, then I got 4.5ghz, and that's the real deal all the time on all cores.

[mettelus]

Some applications can also tap into the UEFI directly, the most concerning I have seen is Corsair's cooling app. That set my CPU target to 5.1GHz, and the system started cycling the cooling system like a jet plane ramping up and down. I disabled the app, but left the drivers installed to prevent recurrence.

It is good to check the UEFI from time to time if things seem odd. I ended up locking mine at 29% OC, and that is actually displayed on the splash screen at startup (ASUS MB). I am not sure if other MB do similar, but is nice to verify.

If it is simply the Turbo mode doing its thing, I wouldn't get worried for it unless the system misbehaves. Systems spend a lot of life at relatively low CPU usage, so that mode allows the machine to shift gears as needed.

[bitflipper]

The dirty secret of the chip industry is that there is no physical difference between CPUs (or any other type of IC or transistor) that differ only in rated clock speed. They all come out of the same oven, but are subsequently tested to see how fast each one can go before it craps out and then labeled accordingly.

The whole overclocking thing began when users realized that the manufacturers were being conservative with those speed ratings, and consumers could claim a bit of that margin of safety back by intentionally clocking CPUs a little higher. A reasonable gamble if you're not doing anything critical on your computer, such as playing video games, and it was gamers who originally popularized the practice.

This is separate from the heat issue. The faster a chip runs, the harder it is to dissipate heat. Too much heat and you get premature physical failures. 

Manufacturers adopted a strategy inspired in the 1920's with the invention of the first electric cash register. A strict calculation of heat and power requirements dictated that a cash register should have an enormous electric motor, making electrification impractical. But an engineer named Charles Kettering showed that as long as the motor wasn't running continuously it could be severely overloaded and not burn up. Thus the concept of "duty cycle" was born, enabling such modern wonders as small but blindingly-bright LED lights.

[craigb]

8 hours ago, bitflipper said:

The dirty secret of the chip industry is that there is no physical difference between CPUs (or any other type of IC or transistor) that differ only in rated clock speed. They all come out of the same oven, but are subsequently tested to see how fast each one can go before it craps out and then labeled accordingly.

The whole overclocking thing began when users realized that the manufacturers were being conservative with those speed ratings, and consumers could claim a bit of that margin of safety back by intentionally clocking CPUs a little higher. A reasonable gamble if you're not doing anything critical on your computer, such as playing video games, and it was gamers who originally popularized the practice.

This is separate from the heat issue. The faster a chip runs, the harder it is to dissipate heat. Too much heat and you get premature physical failures. 

Manufacturers adopted a strategy inspired in the 1920's with the invention of the first electric cash register. A strict calculation of heat and power requirements dictated that a cash register should have an enormous electric motor, making electrification impractical. But an engineer named Charles Kettering showed that as long as the motor wasn't running continuously it could be severely overloaded and not burn up. Thus the concept of "duty cycle" was born, enabling such modern wonders as small but blindingly-bright LED lights.

Spot on!

This was very apparent when AMD was first trying to compete with Intel.  Intel's chips had a good percentage of "error" headroom allowing decent overclocking, but AMD's had VERY little since it was trying to make their chips seem as fast as Intel's.

[kitekrazy]

Mine eventually creeped up to 5ghz.   Maybe I should have done some DAW work.