I recently moved my PC into an Antec Flux M case. The build worked normally during several test boots, and the only new connections were the case fans, their RGB lighting, and the front-panel I/O cables. Shortly after starting the computer today, I saw smoke coming from the case, so I shut it down and disassembled it enough to inspect the wiring. The reset-switch cable had melted along much of its length rather than appearing damaged at one isolated point. I checked the motherboard manual and the power and reset connectors appeared to be attached to the correct pins. The reset button was not being held down; I only pressed the power button, and the cable began smoking within about five seconds. What could cause a reset-switch cable to carry enough current to melt when it should only be a momentary low-voltage signal?
3 Answers
Since the smoke appeared after pressing the power button rather than while the reset button was held, a stuck reset switch is unlikely. The motherboard may have had a fault on its front-panel header that only became apparent when the reset switch was connected, or the case harness could be defective. Check whether the connector was actually the reset-switch plug and not a similarly shaped power, LED, or other I/O connector, and look for melted plastic or signs of a short around the header. The board should be treated as potentially damaged until the cause is found.
A reset-switch lead normally carries almost no current. It is just a momentary switch that briefly connects the motherboard's reset signal to ground, so holding or pressing the button should not make the cable heat up. If the entire wire melted, something abnormal—such as a short, incorrect connector, damaged cable, or failed motherboard circuit—probably placed several amps through it. I would avoid powering the system again, disconnect the case wiring, inspect the motherboard header and cable for shifted pins or damaged insulation, and test with a replacement switch lead or the motherboard's onboard power controls if available.
The reset circuit is a signal input, not a power output, so the motherboard should not be capable of supplying enough current to melt a correctly connected cable during normal operation. A cable failure of this severity points to a wiring fault or a hardware failure. I would document the damage, contact the case manufacturer, and have the motherboard inspected or replaced rather than simply installing another cable.
Related Questions
Lenovo Thinkpad Stuck In Update Loop Install FilterDriverU2_Reload