Is not supported. You can find SATA power to six pin and 4 pin Molex to 6 pin adapters but if you want to jury rig a second PSU you must do that understanding it's risky and no one will tell much more.
Example: https://www.amazon.com/Link-Depot-Express-Adapter-Inches/dp/B000JWTIKC/
I currently have a Dell Inspiron Desktop (Small edition/mini). The graphics card I am trying to Put in is a Nvidia Geforce 1060. The GPU fits, however, the preinstalled Power Source doesn't have a six pin, so it can't power the GPU.
I can't get a new case, But I have an old power supply. Should I switch it out or is there an adapter of some kind to power the GPU.

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