The Mother Board

[mxmone]

Thanks for links. One of them leads to FAS (I have DS14) but I found this: http://www.andovercg.com/datasheets/netapp-ds14-hardware-and-service-guide.pdf In PDF there is no word about fans in PSU Problem with fan? Replace whole PSU
I also know about nmbtc.com site. That's why I know all about cables and signals in fan. Yellow cable is PWM, but this is not a PWM from normal computer. He has 200Hz... Standard PWM have 25kHz (from PDF specs). But to find out what are the real shapes of signals I must buy oscilloscope. On ebay costs only 75,80$ DSO201 I do not have to have a very good oscilloscope. This toy will do the job
Fans I intend to mount, are very quiet. This is Nocuta so even at full speed they will run quieter than previous fans at low speed.