OK so i replaced my power supply in my PC, computer is about 3 years old, i was using my computer normally and one day it wouldn't turn on, so i decided to replace the power supply, no it turns on but right after it goes trough the first blue window where it gives the options of Pressing F10 for System Restore, F1 for Bios, etc..... it gives me a black screen with this massage "Disk Boot Failure, Insert System Disk and Press Enter"

i checked the cables to be plugged in properly and there are no disks inside the dc/dvd drives. I don't know how to fix it.

Could it be that i damaged the Hard drive? when plugging it back in.

thanks in advance.

this won't give you a method to fix and boot from your HD BUT it will give you a method to boot your system and at least try to recovery your data files before trying to fix your HD, See How to recover your folders/files when Windows won’t boot