How to tell prime95 to throttle down cpu consuming
 

Hello

I'm using Prime95 on a company laptop. I like to let Prime95 run, but most of the time, the fan is working at high speed, which isn't usable.
So I need to throttle down the cpu consuming so the fan doesn't have to run at top level speed, but I can't find a possibility, to tell Prime95, to work "slower".
Is there a possibility? If not, I have to stop using the program.

Markus

From undoc.txt in the prime95 directory:
[CODE]If you are running on a laptop or in a hot room and you want to slow the
program down to reduce heat, then you can add this line to prime.txt:
Throttle=n
where n is the percentage of time the program should run. For example,
Throttle=40 means the program will run 40% and be idle 60% of the time.[/CODE]
Hope this helps!

If it is a modern laptop(last ~5 years) one option to make the cpu use less heat is to turn off AVX support using CpuSupportsAVX=0.
This will slow down the calculations quite a bit but it may be better than throttling for you.
When AVX code is detected the cpu voltage is upped which produces quite a bit more heat.

To enlarge on what henry said, throttling is kind of rough on the CPU. It works by turning the calculations on and off by the percentage set. This puts the CPU in a constant heat-and-cool cycle, which causes expansion and contraction, and generally stresses things.

If henry's option isn't available to you, the next question could be if you are running more than one worker. If, for instance, you have a dual core processor, run a single worker on a single core. This will put much less thermal stress on the parts involved, and saves you hearing the fan spin up and down as the load varies.

Other programming possible?
 

After this thread was generated, I have seen, that an other thread was opened in 2009, which I couldn't find by searching ;-)

Now I have tested the CpuSupportsAVX=0 Option, but nothing happens. Fan still blowing and the time is the same as before.
When I throttle down, the one that is described happens. I have to throttle down to 10%, that the fan only goes up a little for a few seconds.

I can also set to a fixed cpu, but this changes nothing. I use a i7 2 CPU Core.

Is there no other possibility to program a less faster thread, so that it consumes 20%, but every time, not only in middle.

Markus

[QUOTE=snoopy78;448150]Now I have tested the CpuSupportsAVX=0 Option, but nothing happens. Fan still blowing and the time is the same as before.[/QUOTE]

Just FYI (since it isn't always clear) CpuSupports lines need to go in local.txt, not prime.txt

As a sanity check did the speed of calculations decrease when you added CpuSupportsAVX=0?

It is possible that the fans would run at full even without the extra heat produced by AVX.
On the CPU options window my cpu shows that it is an i7-6700K. What does yours say?

[QUOTE]I can also set to a fixed cpu, but this changes nothing. I use a i7 2 CPU Core.[/QUOTE]

It is very unlikely that a single core versus 2 cores running would give the same result in terms of heat. If you set up P95 to run the way I suggested, the Test>Worker Windows dialog should look like the attached screen shot. I could be wrong, in that the cooling system might not be able to handle even a single i7 core running flat out. Still, there ought to be some difference in the spin up/spin down fan behavior.

[QUOTE=sdbardwick;448167]Just FYI (since it isn't always clear) CpuSupports lines need to go in local.txt, not prime.txt[/QUOTE]

Thank you. I haven't known this. Why are there different confog files and not only one with different sections?

But at all, it's not affecting my laptop. Fan is still working when I don't throttle.

[QUOTE=henryzz;448168]As a sanity check did the speed of calculations decrease when you added CpuSupportsAVX=0?

It is possible that the fans would run at full even without the extra heat produced by AVX.
On the CPU options window my cpu shows that it is an i7-6700K. What does yours say?[/QUOTE]

I have a i7-2620m. The fan starts normally only, if I'm watching a dvd or using Teamviewer, because this needs the cpu. If not, I can't hear the fan.

[QUOTE=kladner;448177]It is very unlikely that a single core versus 2 cores running would give the same result in terms of heat. If you set up P95 to run the way I suggested, the Test>Worker Windows dialog should look like the attached screen shot. I could be wrong, in that the cooling system might not be able to handle even a single i7 core running flat out. Still, there ought to be some difference in the spin up/spin down fan behavior.[/QUOTE]

I have tested it with this, but without throtteling down to 10%, the fan still runs at high speed and laptop heats up.

Markus