Optiplex 3010 dead fan header

First, which Optiplex 3010? DT (Desktop), MT (Mini Tower) ?

When you recieved this Optiplex 3010, did your friend mention that the fans were not working?

Explain what you mean by "fan headers". Do you mean the motherboard fan connectors?

* Turn the Optiplex 3010 off
* Remove the case cover
* Disconnect the power cable from the Optiplex 3010
* Disconnect and reconnect the fan cables to the motherboard System fan Connector (FAN_SYS1) and CPU fan Connector (FAN_CPU)
* With cover off, plug the power cable back into the Optiplex 3010
* Turn the Optiplex 3010 on. Do the fans spin up?

.5v is  11.5v below the minimum a fan needs to run.

Dell Fan Headers are not wired the same as standard headers.

The Dell fans may or may not use the following 5 wire connector.

P/N: CB-PWM-D5. PWM fan cable adapter converts a PWM connector to a Dell proprietary 4 wires 5 pin connector.

https://www.amazon.com/Pocaton-Female-Socket-Adapter-Cooling/dp/B073XJV5L9/

DELL              STANDARD

1  Yellow   ---------------- Blue

2  Red       ----------------  Yellow

3  Black    ----------------  Red

4   Blue      ---------------- Black

5   NC       

Dell Fan Conversion

By fan header I mean fan connection on motherboard. I tried your suggestions and the chasis fan stil does not spin. The CPU fan is not effected

I cannot tell from the pictures. Are the System fan Connector (FAN_SYS1) and CPU fan Connector (FAN_CPU) using the same number of pins? If yes, can you plug the system fan into the CPU fan Connector (FAN_CPU) to see if it spins up?

I have tested the fan with another PC and it worked

If the chassis fan and cabling worked on another PC, then the connector on the Optiplex 3010 is defective.