Fan rpm problem

[Dave009]

Hey there,

 

I just bought a be quiet pure base 500dx case and it comes with 3 140mm pure wings 2 fans (3 pin, 1000rpm).

 

When I was adjusting the rpm in the bios I noticed that one of these be quiet fans is at 100% but only spins at 925-930rpm, the others are fine with 1000 to 1020 rpm.

I also tried adjusting it with speedfan  but didn't help.

I tried other fan ports, tried slowing down the others but it still wont spin faster than 930rpm.

The fan itself is fine no strange noise or anything like that it just annoys me what could cause this. 

Any ideas?

 

Config:

mobo: Asrock 970 extreme 3

psu: seasonic focus gx 650

cpu: phenom II x4 965 black

vga: sapphire hd 6770 1gb

ram: 2x2gb kingston hyperx 

os: Win 10 64 bit

[Drama Lama]

36 minutes ago, Dave009 said:

Hey there,

 

I just bought a be quiet pure base 500dx case and it comes with 3 140mm pure wings 2 fans (3 pin, 1000rpm).

 

When I was adjusting the rpm in the bios I noticed that one of these be quiet fans is at 100% but only spins at 925-930rpm, the others are fine with 1000 to 1020 rpm.

I also tried adjusting it with speedfan  but didn't help.

I tried other fan ports, tried slowing down the others but it still wont spin faster than 930rpm.

The fan itself is fine no strange noise or anything like that it just annoys me what could cause this. 

Any ideas?

 

Config:

mobo: Asrock 970 extreme 3

psu: seasonic focus gx 650

cpu: phenom II x4 965 black

vga: sapphire hd 6770 1gb

ram: 2x2gb kingston hyperx 

os: Win 10 64 bit

 

When the fans are produced they often don’t have all the same max rpm 

( there are just some fans that function less than others)

(correct me if I’m wrong)

[LogicalDrm]

Usually rpm is given with +-10% accuracy. 10% of 1000rpm is 900rpm, so range of max rpm would be 900-1100rpm.