SPCR

i have a corsair case with 3 front fans with blue led and a top 20cm fan (i think) all use the old legacy 4 pin legacy.

there are 3 such fans and my own 2-pin 120mm fan, the 3 fans each have a 4-pin with a pass through

using a pass through molex 4-pin with 3-pin fan connector i connect 2-pin 120mm fan

using a pair of pliers i cut throught he very hard plastic and then reversed the connection on the power molex from PSU a corsair PSU to fans, from power to the first one, but the other 2 are normal.

now the 2-pin 120mm fan works fine, it whirs and is almost silent.

the led fanlights up very dim but visible

but none of the 3 case fans are running.

at normal 4-pin molex alignment it works but too noisy for my taste.

can this be made to work somehow?

dan wrote:using a pair of pliers i cut throught he very hard plastic and then reversed the connection on the power molex from PSU a corsair PSU to fans, from power to the first one, but the other 2 are normal.

This I have difficulties to envision.
Can you provide a picture or drawing of the cable arrangement?

Olle P wrote:

dan wrote:using a pair of pliers i cut throught he very hard plastic and then reversed the connection on the power molex from PSU a corsair PSU to fans, from power to the first one, but the other 2 are normal.

This I have difficulties to envision.
Can you provide a picture or drawing of the cable arrangement?

sure!

i take this




i cut incisions into the plastic

turn it upside down

connect with this


5 volts this way, LED light up but fans don't whirr and spin

everytime i post here i get this


Error 524 Ray ID: 3f761af324307ad0 • 2018-03-06 16:14:20 UTC
A timeout occurred

Ignore the timeout and just close the tab after hitting "submit".

Your pictures don't show how the cables are drawn between the connectors/pins, which is my concern.

Olle P wrote:Ignore the timeout and just close the tab after hitting "submit".

Your pictures don't show how the cables are drawn between the connectors/pins, which is my concern.

i just turn it upside down and plug it in, to get it to fit i cut incisions into the plastic,

Now I think I understand:
You're essentially feeding 5V on the 12V input and 12V on the 5V input on the fans.
Then the problem can be assumed to stem from having 12V on the 5V line, causing problems with some regulator.