What is POST?

Power-On Self-Test runs before any OS loads. If it fails, nothing appears on screen.

Checklist in order

  1. Monitor and cable — swap cable, try a different port (DisplayPort vs HDMI), test monitor on another machine.
  2. GPU seated — reseat the GPU firmly. Check the PCIe power connectors.
  3. RAM — remove all sticks, clean gold contacts with an eraser, reseat. Try one stick at a time in slot A2.
  4. BIOS speaker / POST codes — listen for beep codes or read the LED POST code display on the motherboard.
  5. CPU power connector — ensure the 8-pin (or 4+4-pin) EPS connector at the top of the board is fully seated.
  6. Clear CMOS — remove the CMOS battery for 30 seconds or use the CLR_CMOS jumper.
  7. Minimal boot — disconnect everything except CPU, one RAM stick, and GPU. No drives, no USB, no fans beyond CPU.