After dusting my PC, I removed the Intel stock cooler from my i5-6400 and had trouble reinstalling it because one of the plastic push-pin clips broke. Since then, the computer powers on and the CPU fan spins, but there is no display and the case power button does not light up. A red CPU diagnostic LED is lit on my MSI B150M PRO-VHD motherboard. The fan is connected, the RAM and processor have been reseated, I tested different RAM configurations, and I also reset the CMOS. Could the broken cooler clip be causing the problem, possibly because it is not applying even pressure to the CPU?
1 Answer
The broken plastic clip itself should not electrically prevent the system from booting. However, if the cooler is mounted unevenly or is pressing on the CPU at an angle, it could interfere with contact in the socket. Remove the cooler, inspect the CPU and socket for bent pins or debris, reseat the processor, and reinstall the cooler with even pressure. Also check that the motherboard’s 8-pin CPU power connector and 24-pin power connector are fully seated. Do not run the system with the cooler loosely attached.
Uneven pressure is possible, but the most important thing is to inspect the socket carefully. A shifted CPU or bent socket pin can trigger the CPU warning light even when the processor itself is fine.