I connected a USB Type-A to USB Type-C cable to a front USB port on my PC. The cable suddenly sparked and burned, and the computer shut off or stopped responding. The USB-C end was not connected to anything. Now the PC will not turn on. The system uses a Montech XT M3/M25 case, MSI B550M VC Pro WiFi motherboard, Ryzen 5 5500, Radeon RX 5700 XT, WD Black SN810, 16GB Digital Storm CL16 memory, a stock Wraith Stealth cooler, and a Raidmax Cobra 650W power supply. What should I check, and is the hardware likely damaged?
2 Answers
The power supply may have detected the short and activated its protection circuit. Unplug the PC from the wall, switch the PSU off, hold the case power button for about 20 seconds, then reconnect it and try once. If you smell burning, see damage, or it still shows no signs of life, stop testing it and don’t keep cycling the power.
A USB cable sparking like that usually means there was a short or a damaged port or cable. Since the Type-C end was disconnected, the front USB wiring, motherboard header, or the cable itself could be at fault. The motherboard may be damaged, and the PSU or other components could be affected too. Inspect the front-port connector and motherboard for scorch marks, but avoid plugging in another cable or using the system until the fault is identified.
The USB-C end wasn’t connected to anything when the cable sparked, which makes me worried that the front port or its wiring shorted internally.