there is a way to increase the CPU usage?

[v44n]

Hello, I am new in this forum and I am using Prime95 for searching new primes numbers. I have a intel i7 5820K. I am searching for a factor but I only got 50% CPU usage, there is a way to increase the CPU usage?

Thank for you time!

PD: I am not sure where to post this in the forum.

Denis Vergara.
Buenos Aires Argentina

[Uncwilly]

Welcome. Hope that you are enjoying searching for primes.

It is likely that 1 of 2 things is happening for you to see 50% usage.

1. Windows is seeing Hyperthreading cores as real cores (they are not). And is reporting usage based upon that. In reality you are using the actual cores 100%.

or

2. You have the settings not quite right in Prime95. Which version are you using? From the menu, when you open up Test -> Worker windows, what values do you see there?

With that, we can figure out how to make sure to the most from your machine.

[23Chaos23]

same deal here, running a 3630QM i7 clocked at 3192.76MHz (could go higher but im capped thanks to thermal limits)
I can only get 1 worker running and it only uses half the Log CPUs for each Phys CPU
is there a way i can dial in the settings for it to use the cores and Log CPUs correctly?
screen cap of what im seeing
64bit OS win 10, W64 P95 v28.9 build 2

[S485122]

Hyper-threading (two different processes or threads sharing one core of a CPU) can be useful. ... if the processes running are not optimised to use the whole capacity of the core.
In the case of Prime95 the program has been optimised to use the capacity of the current CPUs to the full.
Having two processes or threads trying to use the same hardware at the same time will slow down both of the threads.
Barring some very rare exceptions the prime95 program is more efficient using only one thread per core. This will show in Taskmanager as a only half the cores being used or 50 % utilisation.
You can adjust the number of workers and threads used via the menu of the program or by modifying the configuration files (read the undoc.txt file to know what is possible.)
As a conclusion, Your hardware is used 100 % by Pime95 even if Taskmanager shows less and this is especially true on hyper-threaded CPUs.

Jacob

You can also search the Internet about hyper-threading, for instance Wikipedia has an article about Hyper-Threading.

[23Chaos23]

Originally Posted by S485122

Hyper-threading (two different processes or threads sharing one core of a CPU) can be useful. ... if the processes running are not optimised to use the whole capacity of the core.
In the case of Prime95 the program has been optimised to use the capacity of the current CPUs to the full.
Having two processes or threads trying to use the same hardware at the same time will slow down both of the threads.
Barring some very rare exceptions the prime95 program is more efficient using only one thread per core. This will show in Taskmanager as a only half the cores being used or 50 % utilisation.
You can adjust the number of workers and threads used via the menu of the program or by modifying the configuration files (read the undoc.txt file to know what is possible.)
As a conclusion, Your hardware is used 100 % by Pime95 even if Taskmanager shows less and this is especially true on hyper-threaded CPUs.

Jacob

You can also search the Internet about hyper-threading, for instance Wikipedia has an article about Hyper-Threading.

thanks,

[v44n]

Thanks of the information guys! S485122 and Uncwilly

This is my config on prime95:

http://prntscr.com/bpt48f

I am sure its working at 100% but I do not trust to the task manager

[LaurV]

There is no benefit in using a higher-than-1 priority. Set it back to 1. Using 10 will make other programs run much slower, with a very low benefit for P95. If you really have some priority conflict, like screensaver, etc, better play with the priorities for that program. Like for example some screensavers will interfere with P95, stealing its clocks, then change the screensaver or use less fish/star/potatoes on the screen, or decrease its priority from the task scheduler, etc. Or if your program has low priority and it is slow due to P95 running (some pdf readers do that, take a while to open large docs) then increase the priority of that program. But let P95 at 1, it is best for your OS.

[retina]

Originally Posted by LaurV

There is no benefit in using a higher-than-1 priority. Set it back to 1. Using 10 will make other programs run much slower, with a very low benefit for P95. If you really have some priority conflict, like screensaver, etc, better play with the priorities for that program. Like for example some screensavers will interfere with P95, stealing its clocks, then change the screensaver or use less fish/star/potatoes on the screen, or decrease its priority from the task scheduler, etc. Or if your program has low priority and it is slow due to P95 running (some pdf readers do that, take a while to open large docs) then increase the priority of that program. But let P95 at 1, it is best for your OS.

Indeed. One thing many people seem to not understand about priorities is that it only changes the order that work is done, it doesn't change the total amount of work done, or the time need to do the work. So, yeah, if you make P95 run at realtime priority then all other apps/programs/etc. will have to wait for P95 to finish before they can run.