Power-on is not the same as POST
Fans and lights can still appear normal while the platform fails much earlier in the boot path.
New PC won't POST
This page is for the moment after a new build powers on but never reaches a usable boot state. The goal is to help readers narrow the problem down with minimum-boot checks, debug-light clues, and a calmer process before they assume a part is dead.
Minimum-boot testing reduces noise
One stick of RAM, the intended video path, and the smallest hardware set often make the next clue clearer.
Debug indicators matter
Board LEDs, beep patterns, and repeat behavior can help separate memory, CPU, display, and firmware paths.
Keep the diagnosis small
- Reduce the system to the minimum parts needed for a basic POST attempt.
- Check memory one stick at a time in the slot the board documentation expects.
- Watch for debug LEDs, beep codes, restart loops, and any change when hardware is simplified.
- Review CPU support and BIOS expectations before assuming the board or chip is bad.
Keep the next decision practical
When it becomes active troubleshooting