View Full Version : Zalman CPNS7700-ALCU CPU Cooler

Phil B
27-09-2005, 09:45 PM
Has anyone else got one of these?
The reason I ask is, although it's a lot quieter than the stock fan, it still makes a moaning noise when set on the lowest speed. With all the ads & reviews I read, I was expecting almost silence. There's no noise from the fan as far as air movement goes. The fan motor seems to have a strong magnetic field, ie if I spin it with my fingers it doesn't stop smoothly, this I suspect would be the reason for the noise.

Feedback would be appreciated, I don't want to look like a complete plonker at the computer shop.


27-09-2005, 10:59 PM
"Does not generate noise or vibration in Silent Mode"
This was accoeding to the specs.
So go ahead and whinge in the shop....

27-09-2005, 11:20 PM
i suspect the small vibration the van is makeing is amplified by the case. cheak if the motherboard backing plate is vibrating.

otherwise it could be an out of balance fan.

Phil B
28-09-2005, 08:40 PM
Back to the shop then. I know there's nothing wrong with the mounting, I had to do some cutting of the case internals to get it in, nothing structural. Turn the speed up & the tone goes up with it, no panel vibration.

I know what I'll be doing on Saturday now


Murray P
28-09-2005, 11:29 PM
Hell, you should be vertually silent with a 120mm fan sitting on your CPU. Whats the lowest speed setting, around 1200-1600 it should make no discernable sound, if it's running at 2000-2200 you'll hear it.

Zalman make some good products (I have a couple of cnps copper flower coolers), but I think of late they've been run over by a couple of the other crowds.

Phil B
29-09-2005, 10:32 PM
Hi Murray
The fans air movement isn't noisy, it's the motor. I emailed the shop & have got no reply, if I don't get one tomorrow i'll be making my feelings felt & heard on Saturday. Lets just hope their customer service is as flash as their shop. Hopefully I just bought a lemon & it'll be sorted out. The fans lowest speed is 1300.

Graham L
30-09-2005, 05:16 PM
It is normal for a brushless "DC" motor to feel odd (not "smooth") when turned by hand. It's called "cogging", and is caused by the fact that it's really a three phase motor with PM field. The rotor poles are strongly attracted to the field pole pieces. It is more pronounced on stepping motors.