If black and yellow doesn't work, then use trial and error. Presuming it's similar to other Lenovo models: (https://forums.lenovo.com/t5/ThinkCentre-A-E-M-S-Series/ThinkCentre-front-panel-connector-power-audio-and-USB-pinouts/td-p/190651,
If black and yellow doesn't work, then use trial and error. Presuming it's similar to other Lenovo models: (https://forums.lenovo.com/t5/ThinkCentre-A-E-M-S-Series/ThinkCentre-front-panel-connector-power-audio-and-USB-pinouts/td-p/190651,