fan adapters and sensors

[pqwoerituytruei]

This is how i have my fan wired

my sensor works when using 5/12 v but when i use 7v it reports 0rpm and my my fan barely spins if at all
how do i make it work when using 7v should i connect the +5 to ground with a 10k resistor or something?
edit: specs in sig are outdated using a i5-4690k@stock+Z97 asrock board

 

[mrsteve0924]

i'm no expert but why is there a 12v and 5v going to the fan? should just be a 12v and ground no? the fan controller will step down the voltage on the 12v line to reduce speed.

 

[ehume]

Using a 7v adapter, you can never get the rpm reported to the mb. I have tried it many times -- I have adapters for this. I believe the problem comes because both the 5v line and the 12v line are positive. Sure, you get a flow differential of 7v, and that can turn a fan. But forget rpm reporting.