[SOLVED] Water cooler, clicking sound during desktop tasks; stops with increased load.

[phone38149]

My water cooler produces a fast, repeating clicking sound during low processing use. When I open a webpage the sound stops during the loading phase (a few seconds). When an application is loaded the same occurs. When a processor-intensive application is running, such as a game, the sound stops.

I have stopped all the fans. I've moved (angled) the entire case. The tubes are horizontal.

Any ideas?
Thank you for helping.

 

[phone38149]

Is there an option to adjust the motor speed, do you think? Is the cooler failing?

 

[phone38149]

I changed the curves of the pump fan. Made it run faster (where's there's no noise).

 

[Karadjgne]

Wait. What aio are you using? There's only a couple of AIO's designed for variable duty pump speeds, all other pumps should be running full speed at a dedicated 12v, non-pwm. Even the variable pumps don't operate on a curve, they are software controlled to respond to liquid temps and fan duty cycle.