Hello! It sounds like you are encountering some issues after upgrading your CPU to an AMD A10 5800k. The symptoms you described, such as the system turning on briefly and then shutting off or booting into Windows but then turning off after a few seconds or minutes, could be due to various reasons. Here are some troubleshooting steps you can try:
1. Check Compatibility: Make sure that the AMD A10 5800k is compatible with your motherboard. Check the motherboard's specifications to see if it supports the new CPU.
2. Check Power Supply: Insufficient power supply can cause the system to behave erratically. Make sure your power supply unit (PSU) is providing enough power to support the new CPU.
3. Thermal Paste and Heatsink: Ensure that the CPU cooler is properly installed with the correct amount of thermal paste. Overheating can cause the system to shut down unexpectedly.
4. BIOS Update: Check if your motherboard's BIOS needs to be updated to support the new CPU. Sometimes, a BIOS update is required for a new CPU to work properly.
5. Reset BIOS: Try resetting the BIOS settings to default. Incorrect BIOS settings can sometimes cause instability issues.
6. Memory Compatibility: Make sure that your RAM is compatible with the new CPU. Check the RAM speed and compatibility with your motherboard.
7. Check for Bent Pins: Inspect the CPU socket for any bent pins that may be causing poor contact between the CPU and the motherboard.
8. Reinstall the CPU: Try reseating the CPU to ensure it is properly installed in the socket.
If you have tried these steps and are still experiencing issues, it might be helpful to consult a professional technician for further assistance. Let me know if you need more help!