Min computer kan ikke starte

Forleden dag slukkede jeg min computer normalt. Næste dag da jeg startede den skrev den sådan her:

Searching for Boot Record from SCSI..Not Found

Boot Failure
Reboot and Select proper boot device or insert Boot Media in
selected Boot device
Press any key when ready

Searching for Boot Record from Floppy..Not Found
Searching for Boot Record from IDE-0..Not Found
Searching for Boot Record from BBS-0..Found

For realtek RTL8139(X)/8130/810X PCI Fast Ethernet Controller v2.12a(011210)
PXE-E61: Media test failure, check cable
PXE-M0F: Exiting PXE ROM.

Searching for Boot Record from SCSI..Not Found

Boot Failure
Reboot and Select proper boot device or insert Boot Media in
selected Boot device
Press any key when ready

Nogen der kan hjælpe mig?