CPU temp 100C

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CPU temp 100C

Postby Benberk123 » Wed May 27, 2020 7:41 pm

My set up:
Intel i7 8700k
Gigabyte gaming OC 1070ti
Asus h z370 Motherboard
850W Platinum PSU
Adata DDR4 3000 8Gb x2

Hello, I just found out about FAH today from an Avast pop up and decided it would be a great use for my gaming computer. First I figured my set up was pretty much over kill for what seemed like a simple background task so I cranked it up to high thinking my almost top of the line for consumer use CPU could easily handle it. I thought my CPU usage would be like around 5%. When I checked it on task manager I was shocked to see it was around 80%. I was worried about my CPU usage so I put it back down to medium on the FAH browser settings which only made the CPU usage drop to around 70%. I decided to just test what happens when I play a game since my PC is mostly used for gaming running FAH only idle wouldn't be as useful. So after running a game my CPU usage was 100%! And after about 30 mins of gaming i closed the game downloaded CPUID and checked my CPU temp which was at 98 - 100C on all cores, couldn't believe it so I downloaded Core Temp and it also showed 100C which is Tj. Max (the game was already turned off for at least 2 minutes by now and it was still showing 100C). I quickly stopped FAH and my CPU temp dropped to around 50-60C within seconds and right now they are idling around 30C. As a side note my CPU temp usually goes to around 70C while running brand new triple A title games, so it is not my CPU or the thermal paste I applied thats causing these temps.

Is it normal for FAH to use over half of your CPU power even on medium settings and make my temps go up to 100C? I really want to help science with my gaming computer but not at the cost of over 70% of my CPU power and at 100C temps...
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Re: CPU temp 100C

Postby JimboPalmer » Wed May 27, 2020 8:12 pm

Welcome to Folding@Home!

I certainly like to keep my CPU under 90 C myself. F@H uses 50% of your CPU threads on Light, all but one thread on Medium and all threads on Full. It is set to Low Priority so it does not impact other programs. (No OS yet made can set the priority of GPU programs)

If you like you can get a finer control by picking the exact number of threads you want.

Your Intel I7 8700K has 12 threads so you can choose between 1 and 12, but the underlying science code F@H uses, called GROMACS, hates large Prime numbers. (3 is never large, 5 is sometimes large, 7 is always large)

https://ark.intel.com/content/www/us/en ... 0-ghz.html

One thread is devoted to your GTX 1070 ti to keep it fed with data. Leaving you 11.

So 1,2, 3, 4, 6, 8, and 9 threads (F@H calls them cpus) are very safe choices while 5 and 10 are less safe. 7 and 11 are bad choices.

Assuming you run Windows, here are step by step directions to adjust thread use. (You can lower thread use at any time, increasing the number of threads only takes effect on the Next Work Unit)

In the taskbar to the lower right of the screen, you should see a F@H molecule icon, click it (you may need to click an Up Arrow to see it ^)

The second item in this menu is Advanced Control, click it

On this screen to the left is a Configure button, click it

Now you get a screen with a Slots tab, click it

On this white field should be a cpu item, click it and then click edit

By default F@H set the number of CPUs to -1 meaning let the software decide.

You can enter any number from 1 to the number of threads your CPU supports.

If you have GPUs, F@H reserves one CPU per GPU to feed it data across the PCIE bus.

Type the number you want, and click save.

So I would try 6 and see if that makes it cooler, then adjust to fit the temperatures you want.
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Re: CPU temp 100C

Postby Benberk123 » Wed May 27, 2020 9:55 pm

Okay thanks for the tips. I will try setting it to 6 and check it out again. By the way I forgot to mention that I had a cooler master hyper 212 evo with 120mm Corsair 2000 RPM fan. Its not as good as liquid cooling but it is one of the best air coolers in my opinion.
I will check it out and let you know if I am still getting extreme temps.

Also don't you think its a bit much to use 50% CPU power on light? I would have assumed it used less than 5% on my CPU.
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Re: CPU temp 100C

Postby Joe_H » Wed May 27, 2020 10:42 pm

The settings on the slider date back to when most processors for "@home" type computers had 4 or less CPU cores. HT technology or the AMD semi-equivalent might double that, but those were the exceptions.

The folding software uses the resources assigned to it fully, so even if only one CPU thread was assigned you would see a bit more than 8% utilization. The software runs at the lowest priority so anything else would use resources first.

With a processor that has HT enabled, you will find it runs cooler if you limit F@h processing to the number of actual cores. The extra circuits to utilize the HT threads adds to the heat generation of the processor by a noticeable amount. Limited use of those by other processes will not add much more heat.

As for the high temperatures, there are a number of things that could contribute to that even with an adequate cooler. Things that persons have reported back to here have included improper application of transfer paste, cooler slightly tilted when mounted, and needing to adjust the fan curve. Overclocked processors also can create more heat than the TDP rating might indicate.

Or there is the problem I and others ran into with the prior generation Kaby Lake processors, Intel did a poor job of consistently attaching the lid and placing the heat transfer compound between the chip and the lid. From what I have read, that may also be a problem with your generation of processor.

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Re: CPU temp 100C

Postby HugoNotte » Thu May 28, 2020 8:01 am

You mentioned that running brand new triple A games doesn't cause your CPU to heat up as much as running FAH does. FAH CPU Wus use AVX, which makes your processor work much harder per cycle than most other software, creating more heat.

Check your cooling system, as mentioned. The quality and way of application of thermal paste for the CPU cooler might make quite a difference. Airflow inside the case is often an issue so is dust. Maybe have a look and clean everything and try running the PC with the left panel off.
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Re: CPU temp 100C

Postby Rel25917 » Thu May 28, 2020 4:56 pm

Benberk123 wrote: I would have assumed it used less than 5% on my CPU.

Why would you assume this? Projects would take decades at that rate. If I download software that does scientific calculations I would expect 100% cpu use.
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Re: CPU temp 100C

Postby jrweiss » Thu May 28, 2020 9:33 pm

Benberk123 wrote:Intel i7 8700k
Gigabyte gaming OC 1070ti
Asus h z370 Motherboard
850W Platinum PSU
Adata DDR4 3000 8Gb x2

Is it normal for FAH to use over half of your CPU power even on medium settings and make my temps go up to 100C? I really want to help science with my gaming computer but not at the cost of over 70% of my CPU power and at 100C temps...

Yes. As previously explained, F@H actually stresses your CPU and/or GPU much more than most other programs, including games. In fact, most modern games stress the GPU MUCH more than the CPU.

Again, as previously advised, setting the CPU slot to 6 cores should help significantly. However, you may have to look into your rig to ensure your overall cooling solution is working properly.

Your GPU burns 180 Watts or so at full output. If you note the alignment of the cooling fins, it does NOT exhaust most of the cooling air out the card's backplane slots, but just back into the case. So all that hot air has to go someplace. If it can't escape earlier, it will be flowing through your CPU cooler, limiting its effectiveness. To help it:

Ensure you have "positive pressure" in your case. That means the total airflow of intake fans is greater than the total of exhaust outflow. Don't forget to add the PSU fan into the equation. This will allow excess hot air to find the closest slots to exhaust from the case.

Ensure the backplane covers adjacent to your GPU card are slotted, not solid. This will help direct that hot GPU exhaust air directly out the backplane instead of up into the CPU area of the case.

Ensure you have as much INTAKE air as possible for your case. Dual, efficient 120 or 140mm fans should be the minimum. I like Noctua fans for their capacity and silence, but you may have other choices.

Your CPU cooler should be directing its fan exhaust directly into the rear or top case exhaust fan. If your case does not easily support an AIO water cooler, an bigger CPU cooler like the Noctua NH-D15 may help.
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Re: CPU temp 100C

Postby Joe_H » Thu May 28, 2020 11:06 pm

The Cooler Master Hyper 212 EVO mentioned is rated for a maximum of 150 W TDP, but a number of testers have said 140 is more doable. The i7-8700K can exceed 135 W when overclocked, as compared to the nominal 95 W figure for standard clocking. So a better cooler or improvements in airflow may be called for as mentioned above.
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Re: CPU temp 100C

Postby NRT_AntiKytherA » Fri May 29, 2020 7:39 am

I second that, the Hyper 212 EVO is pretty crap for unlocked high TDP processors, I wouldn't bother using on anything with a TDP rating north of 100W.
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Re: CPU temp 100C

Postby foldy » Fri May 29, 2020 8:36 pm

The problem is FAH uses CPU AVX instructions which generate more heat.

Your CPU fans should get loud when your CPU reaches such high >90°C temperatures, did they?

You can get a better CPU cooler like "Thermalright true spirit 140" which can cool 250 watts overclocked CPU silent.

Or in UEFI/BIOS find the AVX offset setting and scale it down.
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Re: CPU temp 100C

Postby Paragon » Sat Jun 06, 2020 2:34 pm

Thanks for joining! That's a nice rig, it should help a lot!

My 2 cents:

Folding@home on your setup will make the most use out of the GPU, with some secondary points coming from the CPU. So, optimizing it for the GPU will be your best bet. My personal preference (for Windows) is to leave one full CPU core free to feed the GPU, and to also leave one full CPU core free for all the dozens of background tasks your machine executes. This will provide more than enough CPU headroom to feed the card + use the system. So, in your case, setting CPU core count to 4 will still let you do some CPU work (necessary for F@h because some molecules only can be solved on the CPU). This will also make sure you are nowhere close to a bottleneck on the GPU.

One thing that also hurts Folding@home efficiency (PPD/Watt) and causes high temps is the automatic overclocking that the CPU does (turbo boost or core performance boost). This cranks up the clock rate and voltage, resulting in more PPD, but also way more power consumption and heat. For folding 24/7, I like to disable turbo core in the BIOS. This forces the CPU to run at the stock max speed (no boosting to silly high voltages and clocks). It will result in 30-40 watts less power consumption, and 10 degrees c or so cooler temps. Yes the machine will make less overall PPD on the CPU, but GPU folding (where most of your points will come from) will be unaffected. Your power bill will be less, your computer will be cooler / quieter, and if you live in a hot climate, it won't fight your air conditioning as hard.
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Re: CPU temp 100C

Postby HaloJones » Sat Jun 06, 2020 2:59 pm

Is your 1070ti folding? That is where the majority of your contribution can come (counted in points). A 1070ti will hit 800K ppd if left to run 24/7. A GPU is also designed to have pretty efficient cooling from the factory so when running folding it will maybe get a little louder but should cope with the heat pretty well.
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