What are the real benefits of semi-fanless mode?

[IIIIIIIIII]

I know this as an extension of fan life, but is there any other reason?

 

Also, some argue that the fan's operation when escaping from fanless mode, rather, significantly shortens the life of the fan. Is it true?

[Moonzy]

4 minutes ago, IIIIIIIIII said:

is there any other reason?

noise, which arguably is more important to me

since if fan dies i can strap on a case fan or something

 

5 minutes ago, IIIIIIIIII said:

some argue that the fan's operation when escaping from fanless mode, rather, significantly shortens the life of the fan. Is it true?

depends on bearing type, i would say

[IIIIIIIIII]

8 minutes ago, Moonzy said:

noise, which arguably is more important to me

since if fan dies i can strap on a case fan or something

I know this too, but I didn't deliberately write it because of some bad cases

 

8 minutes ago, Moonzy said:

depends on bearing type, i would say

Can you tell me the difference between bearings for my question?

[Moonzy]

1 minute ago, IIIIIIIIII said:

Can you tell the difference between bearings for my question?

im not too into that field so i cant say much

 

but some bearing require the fan to spin up before the fluid spreads, so the starting up phase may wear it out

[GoldenLag]

22 minutes ago, IIIIIIIIII said:

but is there any other reason?

marketing and i suppose idle noise, but an idle PSU is inaudible anyways (with a properly configured fan profile)

 

honestly i just suggest turning "semi-fanless" operation off most of the time, if its an option. 

[Guest]

39 minutes ago, GoldenLag said:

an idle PSU is inaudible anyways (with a properly configured fan profile)

Not if you're German.   

 

A more expensive design can be quieter at lower loads.  But if the fan needs to spin faster at higher loads, the number of windings required prevent it from spinning slower at lower loads.  You can implement a PWM to correct this, but that's a cost adder.  Also, a lot (most) of the driver ICs (the hall effect fan motor controllers) will cause an arc between the stator and coil that makes a "buzz", "buzz", "buzz" noise at low RPMs. You also wouldn't want to use a DBB at those lower RPMs because that's when you get the annoying "click", "click", "click" noise.

 

[Sakee__]

3 hours ago, jonnyGURU said:

Not if you're German.   

 

A more expensive design can be quieter at lower loads.  But if the fan needs to spin faster at higher loads, the number of windings required prevent it from spinning slower at lower loads.  You can implement a PWM to correct this, but that's a cost adder.  Also, a lot (most) of the driver ICs (the hall effect fan motor controllers) will cause an arc between the stator and coil that makes a "buzz", "buzz", "buzz" noise at low RPMs. You also wouldn't want to use a DBB at those lower RPMs because that's when you get the annoying "click", "click", "click" noise.

 

Would a motor driver with field oriented control instead of hall effect be of any use on this occasion?

[Guest]

6 hours ago, Sakee__ said:

Would a motor driver with field oriented control instead of hall effect be of any use on this occasion?

Yes!  But that would be more expensive than a decent hall effect IC.  There are more robust hall effect ICs that don't buzz and are still cheaper than a FOC, but heaven forbid the fan manufacturers (or their customers) pay a little extra for it.