[SOLVED] Core count or clock speed

[Amddefector]

Hi thanks for looking.

As the title says what would you consider more more important... Cores/threads or clock speed?

In terms of use of the machine apart from server level we want to use it for everything a computer can be used for.

 

[helpstar]

cannot be answered with a simple: the cores are more important or the clock speed is more important.

both are very important

 

[Unolocogringo]

Depends on the software you are running.
Some software is single/dual core. This will like clock speed.
Some software will will use all of the cores/threads available to it. So this software likes more cores/threads.
There is no single answer, it depends on the software you are running.

 

[USAFRet]

Can't be used in isolation.

Pentium IV, 2004 - 3.4GHz clock
https://en.wikipedia.org/wiki/Pentium_4

i7-9700k, 2018 - 3.6GHz clock, turbo to 4.9GHz
https://ark.intel.com/content/www/u...9700k-processor-12m-cache-up-to-4-90-ghz.html

Which CPU is more capable? Is the new i7 at Turbo really only ~40% "faster" than a 16 year old P-IV? No.

 

[Tigerhawk30]

I guess I'd also say what your use case is and if the metrics are micro-intensive to you or not.

At the base of it, it seems that fewer cores equates to higher boost clock speeds while more cores equals less. That said, are you worried about a few hundred megahertz extra with the fewer cores? What's your budget? What kind of cooling solution are you prepared to pay for and mount? So many factors...

That said, mine is built around a 3950X. Highest max speed boost I've ever seen is 4.6GHz. But that's fine with me...not worried about the max speed so much as I am the power of more cores (I mainly use it to churn away at Folding At Home, but also gaming), so I'm fully content with having more resources. I couldn't care less that I won't ever hit 5GHz with it.

It's your money and your vision...fulfill it!

 

[Amddefector]

cannot be answered with a simple: the cores are more important or the clock speed is more important.

both are very important

Yea I know both are important, some apps are more reliant on a high clock speed whereas some or a lot don't need to be at 5ghz but if your using the computer for a multitude of different tasks is it worth going for a CPU with lots of power/ not that many threads or the other way round.
If we say 128 threads at 2.9ghz or 48 threads at 3.8ghz or 16 threads at 5ghz what would you prefer.

 

[helpstar]

because I only use it for gaming, office and multimedia:
16 threads at 5ghz

 

[Amddefector]

I know there's a lot of factors to think about here ie use, what apps, budget, multitasking or single tasking then there's the apps that depend more or GPU performance than CPU performance. I've found that going for more cores at a lower clock speed has always seen a overal performance gain for me personally but that's going from 4 cores to 8 or 8 to 16 and I'm guessing the performance gain was mostly due to windows not using up everything the CPU had to give. But most modern apps make use of these extra cores don't they? And now we can have 64 or more cores is it worth having that many? If a multi threaded application has the use of 8 cores at 5ghz or the use of 64 at 3ghz isn't it effectively gonna be more efficient or doesn't it work like that?

 

[Zerk2012]

In terms of use of the machine apart from server level we want to use it for everything a computer can be used for.

Their no 100% answer to your question as you have asked it everything a PC can be used for changes the answer with using it for different things.

My best answer would be find a happy spot in between cores and speed.

 

[jasonf2]

For simple tasks Clock speed coupled with Instructions per Clockcycle (IPC) are most important. (IE simple math)
For tasks that are easily set up to be broken up and concurrently calculated high core count can be taken advantage of. (IE video transcoding)
In the real world your computer is running a mixture of both. So while you will always see some benchmark improvement from an IPC increase and/or a clock increase you may not see a performance increase by increasing the number of cores. But in certain workloads core count increase will increase performance until the efficiency loss of of splitting and reassembling the workload over take the gains.

From my experience this means that the importance is relative to what you are doing and what processor you are working with. Older AMD chips had great clock frequency, but really bad IPC. So when looking at prior generations clock frequency often means a lot less than the processor benchmark numbers because they relate real throughput. AMD prior to ryzen was churning out lots of high frequency, high core count chips. However in benchmark application Intel at that time was out performing those chips with lower clocks and core counts because IPC was so much better. The only reason that AMD is back is because they increased IPC a bunch. By doing this they are offering high core count with strong IPC and clock cycle and Intel is short on core count. All three pieces are important.
Ceteris Paribus high core counts are best for loads like transcoding or server applications where the tasks can be paralleled easily. High clock frequency is only good if the core design has good IPC. And IPC improvements will always increase performance.

 

[geofelt]

It depends.....

If you have a multiplicity of concurrent apps, then many threads are good.
If you have a well threaded app, then many threads are good. Up to a point where "amdahl's law"
comes into play.
https://en.wikipedia.org/wiki/Amdahl's_law
Typically, a gaming pc can only effectively use 4-6 threads.
You may see more threads active in task manager, but that is windows spreading activity around.
Games such as sims, strategy and mmo will largely depend on a fast master thread.
OTOH if the game is multiplayer with many participants, then many threads can be effectively used.

Then, on core speed... it depends.

Performance of a single thread is determined not only by the clock speed, but also by how many operations per clock the processor can handle. The processor architecture can make a big difference.
The upcoming Intel willow lake architecture has tested out at some 18% better instructions per clock than before. The instruction mix may be important. Some instructions do the work of a whole subroutine, yet count as just one instruction.

The best measure of a prospective processor is how it performs doing YOUR work, or at least something similar.

 

[SamirD]

Here's what I've learned about this in terms of practical use--the higher the single thread performance, the faster the computer will 'feel'; the more cores it has the more 'smooth' everything will run.