Avoid laptop overheating
 

I have a laptop, AMD 5500U,, 2.10 Ghz (boost 4 GHz), 8 GB, 6 core.

I thought this computer could do som useful work when I am not carrying it around. However, whwn I run Prime95, the temperature is around 85 deg C and the fan spins like crazy. I know I can lower the CPU speed a little and I also tried running only one worker. But that didnt help much.

Is there a way to run Prime95 with a much lower speed/temperature and still have the computer responsive för other tasks? Even if it takes a month to do what my main computer could do in five days, still i could be a useful drop in the ocean.

You didn't mention your OS.

If you use Linux with systemd you can use the OS to limit the scheduling.[code]~ sudo systemd-run --scope --uid=1000 --property=CPUQuota=20% ./prime95.exe
Running scope as unit run-r4c2f3c4de18748a8bf2a8715651bb62f.scope.


<! in another terminal to change the time slice !>
~ sudo systemctl set-property run-r4c2f3c4de18748a8bf2a8715651bb62f.scope CPUQuota=70%[/code]

You want this or a similar tool to underclock and tweak settings like limiting boost: [url]https://www.ryzencontroller.com/[/url]

If you let p95 run on a modern laptop 24/7 without taking power limiting steps it's possible it'll damage itself. I have a laptop which has physically bulged slightly above the cpu from where heat started warping the chassis. They want the cpu to suck power so it wins a benchmark to look good on paper, but they also want the laptop to be as thick as a piece of paper, so the coolers are entirely inadequate most of the time.

There’s also control available within Prime95, using the Throttle option for the prime.txt file,
[quote]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.
[/quote]

[QUOTE=cxc;632445]There’s also control available within Prime95, using the Throttle option for the prime.txt file,[/QUOTE]I found this option to produce thermal pulses rhythmically heating and cooling the CPU. I felt it was not good for long term reliability with the constantly changing thermal stresses. Maintaining an even temperature (no matter if high or low, just make sure it is stable) will help it to last longer and stay reliable.

Thank you for taking your time to answer.
I am running Win 11.

I tried the throttle parameter. Both 30 and 40. With 40 the temp varies between 58 and 49 deg C with a period of 10 s. With param 30 the computer runs slightly cooler, maybe I should try to prevent that the processer will boost at 4 GHz now and then.

With these settings my laptop will complete a LL DC 72M range in about 8 days. Not bad I think.

But, as Retina wrote, it could be a long time problem with a temperature change of 10 deg C 6 times a minute. Any idea how to keep the temperatur more stable?

On windows I would probably use a power plan to restrict the max clock rate.
[url]https://www.instructables.com/How-to-Adjust-CPU-Frequency-in-Windows-10/[/url]

I don't know if there is an equivalent in linux. This may be adjustable in some laptop bioses(reducing the TDP is the aim).

I use a cooling pad and a KLIM laptop cooler.

Thanks for all input.
I had been fiddling with the power plans but it had not worked as I wanted. But after Henrys post I tried once again, and now it worked.
The trick was to realize that the base frequency was 2.1 GHz and the boost frequency 4.0. To get a low frequency likke 1.7 I had to fight the boost, i.e. I lowered the frequency to 33 %, the CPU tried to boost and finally I got 33% x 4.0 = 1.7 GHz.
So now the laptop is humming along with a constant 49 deg C, the speed is such that it will make a LL DC range 72M in about 10 days, hopefully unattended.

Thanks all!

[QUOTE=aristofanes;632458]Thanks for all input.
I had been fiddling with the power plans but it had not worked as I wanted. But after Henrys post I tried once again, and now it worked.
The trick was to realize that the base frequency was 2.1 GHz and the boost frequency 4.0. To get a low frequency likke 1.7 I had to fight the boost, i.e. I lowered the frequency to 33 %, the CPU tried to boost and finally I got 33% x 4.0 = 1.7 GHz.
So now the laptop is humming along with a constant 49 deg C, the speed is such that it will make a LL DC range 72M in about 10 days, hopefully unattended.

Thanks all![/QUOTE]

That seems like a good approach. Before I built machines dedicated to mprime, with crazy cooling capacity, I was always fighting with trying to find the best clock. Generally turning off any boost was the best approach. In most cases you are limited by memory bandwidth, so running the cpu faster just makes heat, without much gain. I worry about memory temp as well. I don't know if this is an issue on laptops, but on my systems for doing P-1, with lots of memory, I make sure there is a lot of airflow over the DIMMs.

Also, a machine that runs 24/7, ingests a lot of dust, so w/o good filters it is good to take them apart once in a while and clean out the junk.

Using my laptop is just a small sideproject. On my main computer I also tried to change my clock speed. 5% OC just gave 1% better throughput and some extra heat. But for the memory (DDR4) I got a strict proportionality, i.e. 10% more speed gave almost 10% throughput.

Thank you for sharing tour experiences, I am rather new in this exciting project.

[QUOTE=aristofanes;632471]Using my laptop is just a small sideproject. On my main computer I also tried to change my clock speed. 5% OC just gave 1% better throughput and some extra heat. But for the memory (DDR4) I got a strict proportionality, i.e. 10% more speed gave almost 10% throughput.

Thank you for sharing tour experiences, I am rather new in this exciting project.[/QUOTE]

Prime95 prp testing is nearly always limited by memory bandwidth. If the main machine spends most of its time running P95, consider *under*clocking the CPU a bit to save a bunch of power. Slowing the CPU by 10% might save 16-20% power use (because voltage can be reduced too), with only 1-2% loss in work production. It's worth experimenting with such changes for machines that run these projects 24/7.

[QUOTE=VBCurtis;632472]It's worth experimenting with such changes for machines that run these projects 24/7.[/QUOTE]

Indeed. I won't hire anyone who doesn't know how to do this kind of thing.

My review process is somewhat non-nominal.

Try [URL="https://www.techpowerup.com/download/techpowerup-throttlestop/"]Throttlestop[/URL] to change your PL1 power limit with a lower value.
(This reduces your performance for other heavy tasks, like video encoding, as well. So you may disable Throttlestop temporally when running such tasks)
[URL="https://www.intel.com/content/www/us/en/download/17881/intel-extreme-tuning-utility-intel-xtu.html"]Intel XTU[/URL] or [URL="https://www.amd.com/en/technologies/ryzen-master"]Ryzen Master[/URL] should work too. However I personally dislike XTU because it might lose your setting and revert to the default value on its own, about a month after your tweaking. This happened on quite a bunch of people including me.

Are you using a gaming laptop? Do you use it like a desktop computer instead of carrying it around?

If yes consider a [B]cheap[/B] laptop cooling pad from Aliexpress (spending too much money on this won't help).

Even lifting the rear side of your laptop with 2 Coca-cola bottle caps helps a bit since this increases the amount of air entering your machine.

[QUOTE=leonardyan96;633048]Are you using a gaming laptop? Do you use it like a desktop computer instead of carrying it around?
[/QUOTE]
Thanks for your comment.
In my small homeoffice I have a capable computer. I use it for handling still images and to generate some YT-videos and the unused cycles for prime assignments.

My laptop is used for taking notes etc when I am not at home, however during the summer my laptop mainly sits on its shelf.
Primes on my laptop is just a sideproject. I have lowered its clock to 1.7 GHz, and the laptop now ticks along at a low but steady speed around 45 deg C.