hiya guys how are ya? just a quick question, i bought two YS-TECH FD1238 120mm Fan - 4 Pin totalling (250cfm). i put them on a fan controller. when i turn them up to full power a clicking sound comes out of the mother board and windows freezes. i turn the power down on the fan controller and everything goes back to normal. i thought it might be the fan controller so i connected them direct to the power supply which means full power for the fans, and i got the same problem > what could it be ???

Hi alkis777, welcome to itsallPC

Your problem could mean that one of the fans is defective and shorting out. Try attaching each fan individually and seeing if just one of them is causing the problem.

Otherwise, your PSU is probably to blame. What is the wattage of the PSU, and what sort of system are running?

tried one fan at a time they were ok.
psu: atrix 500w
cpu: pentium d 3.4 (x2) overclocked to 4.01 (x2)
mother board: asus p5nd2 sli
memory: 2g corsair
graphics card: nvidia geforce 7600gt
hard drive: wd 250gb

sorry and 5 fans including the ones causing problems

It's probably your Power Supply Unit then