Asetek idling noise

[Oswaldvv]

Hi all,

Recently got a premade, after a couple of weeks of use the CPU cooling pump started making a rattle noise. The obvious thing to check was for air bubbles so I had a go at the usual shaking the radiator and then dismounted the pump and gave that a light shake too. I then left the pc on its side for a while with the power on.

However this morning I realised that the noise disappears when ramping up the cpu when running an intensive game, and returned when it went back to idling

Could it still be air trapped inside that gets temporarily displaced when cpu is working hard? I'm at a loss now as to what it could be.

The unit is a Asetek 670lt 240mm

 

[Oswaldvv]

How's the radiator mounted in relation to the cooler/pump/reservoir? A picture would help.

Apologies, here is a picture, it was installed by OC so I assumed it's fine

I also include a short mp3 of the sound in question
https://vocaroo.com/17UJuFgYVKWX

 

[Oswaldvv]

Thanks for the ideas, I have been in contact with Asetek and recently OC who are sending out a replacement. The person I spoke to at Asetek guessed there was something hitting the impeller rather than air bubbles from the sound it was making.
Unfortunately the pump speed does not sound easy to change manually, as according to Asetek runs at a constant 2800 rpm. I have no idea why it would stop making the noise on high cpu usage but I might try opening up it up once replaced, and seeing what might be making the noise as I don't have any previous experience with water coolers, will be interesting just to have a look anyway.

Cheers