I have a 700W power supply, but it doesn't include the connector I expected for my case's front-panel I/O. Is there an adapter that lets me connect a peripheral power cable to the front-panel header or I/O slot? My system uses a Gigabyte Z390 motherboard, an Intel i9 KF processor, DDR4 memory, and an AMD 9070 XT graphics card.
2 Answers
The case’s front-panel cables—power switch, reset switch, power LED, and drive LED—plug into the front-panel header on the motherboard, not into the power supply. They normally don’t need a separate PSU connection because the motherboard supplies the required power.
If you’re referring to a special connector from the case, it may be part of a proprietary case or prebuilt system. Don’t force a peripheral PSU cable into a motherboard header; the pinouts are different and could damage the hardware. Please identify the exact case and power-supply models, then compare their manuals or connector diagrams before buying an adapter.

The motherboard and CPU/GPU details alone aren’t enough to identify that cable. The case model and exact PSU model are the important parts here.