What does this light mean and how can I fix it

This is a sub for Pc-Building enthusiasts, where you can get and give help about anything! (Questions, Budgets, Pablo, etc.)
My pc turns on but my monitor says there’s no signal
This is a sub for Pc-Building enthusiasts, where you can get and give help about anything! (Questions, Budgets, Pablo, etc.)Should I go for windows 10 or 11
This is a sub for Pc-Building enthusiasts, where you can get and give help about anything! (Questions, Budgets, Pablo, etc.)I accidentally smudged the thermal paste

This is a sub for Pc-Building enthusiasts, where you can get and give help about anything! (Questions, Budgets, Pablo, etc.)