9 Beeps: ROM BIOS checksum failure
Explanation: The read-only memory (ROM) containing the BIOS program (which is what is running when you turn on the PC and what generates this error) uses a checksum value as a double-check that the ROM code is correct. This checksum is compared against the values in the ROM each time the PC is booted and if there is a mismatch, this code is generated.
Diagnosis: The BIOS ROM chip on the motherboard is probably faulty. It could also be another component on the motherboard.