Hi bro, I got issue here, my PC wouldn't POST even with minimum hardware plugged which is Mobo, PSU, CPU and RAM. It display nothing not even BIOS. It already 4 month after it last successful boot. Last week I've tried reassemble everything and successful to boot and updated the BIOS without any issue. I was able to restart multiple time. The problem is I not yet apply the thermal compound. Then I remove the cooler apply the thermal paste and put back the heat sink. This time the system return to the early state. I can cannot make him alive anymore until today.

My system current spec is
- MSI B250M Mortar
- Intel i5 6600
- Avexir 16GBx2 RAM
- Toshiba 500GB 2.5" HDD

Do you have any suspect regarding my stated?