lower voltage on the chassi fan of Silverstone Grandia GD05B

[Darkpoem]

I am going to build a HTPC with the Silverstone Grandia GD05B but I want to lower the voltage to 7V on the chassi fans as they did in the review of the Grandia here at SPCR

http://www.silentpcreview.com/article1033-page5.html

Is the common solution for this to just to use 12V and 5V cable and use 5V as ground?

I am also going to use the Nexus Value 430W as power source:

http://www.silentpcreview.com/Nexus_Value_430

[wouterr5]

For fans that come with a Molex adaptor, it is a good solution - but looking at the specifications and photos of the gd05, it looks like that's not the case

[Darkpoem]

ok, but what should I then do?

[speedkar9]

The simple solution is to buy or make a fan controller, or use a fanmate to lower its voltage.

Since the fan is 3-pin, you could hard wire the red (3pin) and black (3pin) wires to a molex connector, using 5V (red molex) as ground and 12V (yellow molex) as positive. Then route the RPM wire (yellow on 3pin) and the black (3pin) to the motherboard header for RPM feedback. Be-careful though the 7V hack is dangerous and could ruin your power supply!
http://www.silentpcreview.com/article6-page1.html

[Darkpoem]

Thx speedcar! I am not worried about ruin the power supply so I will try your solution.
I will first put to computer together and see if the noice is anyoing and the computer is working.

BR /Tobias