Can you guys explain the boost clock plz

[Mat1926]

Check this screen of my 7900x while encoding using Handbrake

 

 

Why all the cores are @ 4 GHZ? I thought some will be @ 4.3 and some will be at lower speeds, below 4.0...or am I totally wrong?

[DocSwag]

Because you're using all cores, and the max all core turbo is 4 ghz, is what I would assume.

 

Temps in the 70s also probably contributes to that.

[3 Lions]

You probably have multi-core enhancement on. 

[Jurrunio]

Boost speeds only come in when a few cores are loaded. All core max speed is the base speed.

[Mat1926]

1 minute ago, DocSwag said:

Because you're using all cores, and the max all core turbo is 4 ghz, is what I would assume.

 

Temps in the 70s also probably contributes to that.

I thought if I used all cores few will be @ or higher than 4 and some will be at speeds lower than 4, they will have different speeds....

[Mat1926]

1 minute ago, Jurrunio said:

Boost speeds only come in when a few cores are loaded. All core max speed is the base speed.

Base speed is 3.3 or something not 4.0...right?

[ScratchHacker]

Turbo speed is 4.3ghz so its not reaching that but mce makes all cores run at turbo speed when it can so that is pretty wierd to see them all run at 4ghz

[ScratchHacker]

2 minutes ago, Mat1926 said:

Base speed is 3.3 or something not 4.0...right?

Yea base speed is 3.3ghz

[Mat1926]

My MB is GigaByte Gaming 9, I did not alter any settings in the bios, I noticed the same thing before upgrading to the latest bios F6... I don't have problem with them all running @ 4.0 but I thought that is not what I was expecting...

[i_build_nanosuits]

8 minutes ago, Mat1926 said:

Base speed is 3.3 or something not 4.0...right?

base speed has to be advertised that way because if you are doing heavy AVX instructions on all the cores it might and likely will go as far down as 3,3ghz so intel has to advertise it that way.

Max boost clock is for when only a certain amount of CPU cores are under heavy use, those cores should and will reach the max advertised boost clock.

Now your all core boost is 4.0ghz which is to be expected for this CPU and it's actually pretty good if you ask me.

[Mat1926]

Just now, i_build_nanosuits said:

base speed has to be advertised that way because if you are doing heavy AVX instructions on all the cores it might and likely will go as far down as 3,3ghz so intel has to advertise it that way.

Max boost clock is for when only a certain amount of CPU cores are under heavy use, those cores should and will reach the max advertised boost clock.

Now your all core boost is 4.0ghz which is to be expected for this CPU and it's actually pretty good if you ask me.

I totally agree with you, I don't have problem running @ 4.0 at all....I was only curious.. & thnx for clarifying all that...

[D13H4RD]

The boost clock differs depending on how many cores are worked.

 

My 7700HQ for instance has a maximum advertised boost clock of 3.8GHz. However, its actual multicore boost clock is 3.4GHz when all 4 cores are at work. It will only reach 3.8GHz when a single-core is loaded.

[pyrojoe34]

At stock settings the 7900X can boost all cores to 4.0Ghz simultaneously, If only 4 cores are active you can reach 4.1Ghz and if only two cores are active you can reach up to 4.3Ghz. Turbo boost 3.0 means that the most stable core is pre-determined and that specific core can reach up to 4.5Ghz if the load is on a single core.

 

So when using applications that can use all threads you will get a max of 4.0Ghz, applications that use less threads (meaning some cores are idle) will allow them to reach higher frequencies.

 

When just using the computer normally (not rendering) you should be seeing the speeds on individual cores reach higher than 4Ghz. Is this not happening?

[DocSwag]

46 minutes ago, Mat1926 said:

I thought if I used all cores few will be @ or higher than 4 and some will be at speeds lower than 4, they will have different speeds....

Turbo boost is temperature dependent, I'm guessing that if they went above 4 ghz temps would be in the 80s so it went down to 4 ghz.

[pyrojoe34]

6 minutes ago, DocSwag said:

Turbo boost is temperature dependent, I'm guessing that if they went above 4 ghz temps would be in the 80s so it went down to 4 ghz.

Not only, for CPUs it's also limited by the number of active cores and the power draw. Even if you have the CPU sitting at 50C with great cooling, when you have all cores active it won't go above 4Ghz unless you OC.

 

For GPUs the boost is mostly limited to temperature and power draw and core count doesn't matter.