The extra molex connectors would be to provide additional power to the pci-e slots, because otherwise all pci- slots would be powered from just 2 12v wires in the 24 pin connector. Try turning on the motherboard with just the 24 pin connector and the cpu 4/8 pin connector. It's common for a cable to have 3-4 connectors, usually 2-3 sata and a molex connector. So post your make and model, ad we can tell you which fan type (3-pin or 4-pin) you can use.Your beQuiet power supply has 'peripheral' connectors on it, in which you can plug cables that have a bunch of connectors. IF you decide to replace all those fans, again which fan type you buy depends on what your mobo's headers can do. After that it is up to you to check all your fans from time to time to be sure they are still working.Ĥ. In those cases, you can go into BIOS Setup and tell it to Ignore those fan speed signals. So your mobo may give out warnings that the case fans have failed because they send no speed signal. But your fans do not have any signal output to connect to. You see, a fan speed signal is generated by the fan motor and sent back to the mobo header on Pin #3 where it can be counted for display and monitored for failure. If you so this with custom fan cables as above, you cannot connect a speed signal wire. So, if you want to custom make fan cables as above and use them, FIRST post here exactly what mobo maker and model you have so we can look for the details in its manual.ģ. Some such headers operate only as 4-pin headers using PWM Mode (which cannot control your fans), some operate only in Voltage Control Mode (which can do what you want), and some can be configured in BIOS Setup to do either. The tricky part is that although your mobo's headers have 4 pins, how they do fan speed control can not be deduced from that. It controls fan speed by changing the voltage on header Pin #2, and that is the only way to control the speed of those 2-wire fans you already have. That's the system used for older 3-pin fan types.

This can ONLY work if your mobo's CHA_FAN or SYS_FAN headers operate in Voltage Control Mode.

That, in turn, will mate with a RED wire from the fan itself when you plug it in.Ģ. Pin #1 of the fan connector must go to one of the BLACK wires on the Molex, and Pin #2 must go to the YELLOW of the Molex. With wire cutting and splicing and soldering you could put the female Molex onto the end of the extension cable. The only way I can see to getting such a cable would be to buy a fan extension cable (female to male) and an adapter with a male fan output connector on one end and BOTH male and female 4-pin Molex connectors on the other. I have even tried to figure a way to use two or more cables with adapters to create the right one, but I can't. You want one with a female 4-pin fan connector on one end, and a female 4-pin Molex connector on the other, with proper connections for powering a fan. I have never been able to find the cable you are looking for ready to buy. Even that step requires checking some details - I'll get to that.ġ. But you may have pointed to the best solution - replace all the fans that came pre-installed in your case with 'standard' case ventilation fans. I understand what you want, so I can outline the difficulty and possible solutions.

Molex 4 pin connectors