[SOLVED] running fan at 100%

The Vic

Commendable
Jun 5, 2020
49
4
1,535
hi everyone,

quick disclaimer: i'm a bit of a tech novice so bear with me (hence asking this q).

i run game theory analysis and the software is very cpu intensive. the software allows me to choose the number of threads to run the simulations, obviously the more threads the quicker it runs. most of the simulations take several hours and sometimes i have to leave them to run overnight. The more threads i allow the program to use the quicker it finishes BUT lowering the threads used doesn't lower the fan %, only the CPU usage %. So my q's are;

  1. is it detrimental to my fan or any other components to run at 100% for several hours/overnight?
  2. " " for cpu usage to run at 100% for several hours/overnight?

the temps during this remains at 69 celcius so i think that's fine?

cpu is ryzen 3600 and using wraith prism cooler.

thanks
 
Solution
Most case fans are rated for 40,000 to upto 150,000 hrs MTTF (Mean Time To Failure). That's @ 4.5 years to 17 years at 24/7 usage. Not something you'll really need worry about for years, really, and by that time you'll be in the market for a different cpu cooler, maybe even a platform upgrade and new cpu/cooler.

That's not to say it's guaranteed to last that long, just the amount of time the manufacturer expects it to last.

Cpu fans are controlled by sensors inside the cpu. At certain temps, they will spin faster. Temps are a result of multiple factors, like core usage or speeds or voltage or current usage in any combination. Not necessarily limited to cpu usage which is different to cpu load.

Cpu usage is the amount of resources the...

Dean0919

Honorable
Oct 25, 2017
269
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10,740
  • It's absolutely normal for the fan to run with full speed when CPU is 100% loaded, doesn't matter how many threads are working.
  • No, but it will shorten their lifespan, but not as quickly as you think. I wouldn't worry about it. The only problem might be a bit bigger electricity bill, but I don't know how big, because I never left my computer fully loaded for overnights.
Your temps are also good which plays positively in this scenario.
 

The Vic

Commendable
Jun 5, 2020
49
4
1,535
  • It's absolutely normal for the fan to run with full speed when CPU is 100% loaded, doesn't matter how many threads are working.
  • No, but it will shorten their lifespan, but not as quickly as you think. I wouldn't worry about it. The only problem might be a bit bigger electricity bill, but I don't know how big, because I never left my computer fully loaded for overnights.
Your temps are also good which plays positively in this scenario.
awesome thanks for the response!
 
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Karadjgne

Titan
Ambassador
Most case fans are rated for 40,000 to upto 150,000 hrs MTTF (Mean Time To Failure). That's @ 4.5 years to 17 years at 24/7 usage. Not something you'll really need worry about for years, really, and by that time you'll be in the market for a different cpu cooler, maybe even a platform upgrade and new cpu/cooler.

That's not to say it's guaranteed to last that long, just the amount of time the manufacturer expects it to last.

Cpu fans are controlled by sensors inside the cpu. At certain temps, they will spin faster. Temps are a result of multiple factors, like core usage or speeds or voltage or current usage in any combination. Not necessarily limited to cpu usage which is different to cpu load.

Cpu usage is the amount of resources the cpu uses to get the job done, like ram or Lcache or cores or bandwidth. It's different to how much of the cpu is used. You can have 3 cores at 100% and 3 cores at 50% and still show a 100% usage if the bandwidth and memory controller and Lcache are saturated. Or a 50% usage if they are far from saturated. But those 3 cores at 100% loads are going to jack up the temps with high voltages, high current usage.

Cpus are well capable of running 100% loads continuously. It's the temp while under that load that's important. 69°C, no worries.

If you want to slow fan speeds down, when using such high loads, you'll need a larger capacity, more efficient cooler. (those aren't the same either). The Noctua NH-D15 is a 250w cooler. The beQuiet Darkrock Pro4 is also a 250w cooler, both massive twin fan towers. The Noctua gets slightly better temps because the fan/heatsink combination is slightly more efficient. The Noctua NH-U12A is a 220w cooler, but almost matches both the D15 and the DRP4 for temps because it is very efficient. With the added capacity, the curve ratio of cpu output to cpu temp vs capacity is lower, meaning with any of those 3 coolers you'd be lucky (unlucky?) to see fan speeds over 50% and your temps wouldn't be reaching 69°C.
 
Last edited:
Solution

The Vic

Commendable
Jun 5, 2020
49
4
1,535
Most case fans are rated for 40,000 to upto 150,000 hrs MTTF (Mean Time To Failure). That's @ 4.5 years to 17 years at 24/7 usage. Not something you'll really need worry about for years, really, and by that time you'll be in the market for a different cpu cooler, maybe even a platform upgrade and new cpu/cooler.

That's not to say it's guaranteed to last that long, just the amount of time the manufacturer expects it to last.

Cpu fans are controlled by sensors inside the cpu. At certain temps, they will spin faster. Temps are a result of multiple factors, like core usage or speeds or voltage or current usage in any combination. Not necessarily limited to cpu usage which is different to cpu load.

Cpu usage is the amount of resources the cpu uses to get the job done, like ram or Lcache or cores or bandwidth. It's different to how much of the cpu is used. You can have 3 cores at 100% and 3 cores at 50% and still show a 100% usage if the bandwidth and memory controller and Lcache are saturated. Or a 50% usage if they are far from saturated. But those 3 cores at 100% loads are going to jack up the temps with high voltages, high current usage.

Cpus are well capable of running 100% loads continuously. It's the temp while under that load that's important. 69°C, no worries.

If you want to slow fan speeds down, when using such high loads, you'll need a larger capacity, more efficient cooler. (those aren't the same either). The Noctua NH-D15 is a 250w cooler. The beQuiet Darkrock Pro4 is also a 250w cooler, both massive twin fan towers. The Noctua gets slightly better temps because the fan/heatsink combination is slightly more efficient. The Noctua NH-U12A is a 220w cooler, but almost matches both the D15 and the DRP4 for temps because it is very efficient. With the added capacity, the curve ratio of cpu output to cpu temp vs capacity is lower, meaning with any of those 3 coolers you'd be lucky (unlucky?) to see fan speeds over 50% and your temps wouldn't be reaching 69°C.
unreal response, thanks so much