Intermittent Problems; Hard Disk Drive Problems - Lenovo ThinkCentre M79 Hardware Maintenance Manual

• On computers that have a CD-ROM or CD-RW drive in addition to a DVD-ROM drive, ensure that the
DVD disc is in the drive labeled "DVD".

Intermittent problems

Some problems occur only occasionally and are difficult to repeat.
Solutions:
• Ensure that all cables and cords are securely connected to the computer and attached devices.
• Ensure that when the computer is on, the fan grill is not blocked (there is air flow around the grill), and the
fans are working. If airflow is blocked or the fans are not working, the computer might overheat.
• If Small Computer System Interface (SCSI) devices are installed, ensure that the last external device in
each SCSI chain is terminated correctly. For more information, see your SCSI documentation.

Hard disk drive problems

Select your symptom from the following list:
• "Some or all hard disk drives missing from the Setup Utility program" on page 77
• ""No Operating System Found" message or the system not starting from the correct hard disk drive"
on page 77
Some or all hard disk drives missing from the Setup Utility program
Symptom: Some or all hard disk drives missing from the Setup Utility program
Actions:
• Ensure that all hard disk drive signal cables and power cables are connected correctly.
• Ensure that your computer is configured correctly to support the hard disk drives.
– If your computer is installed with five SATA hard disk drives, ensure that the SATA hard disk drive
enablement module (one to five hard disk drives) is installed.
– If your computer is installed with SAS hard disk drives, ensure that the SAS hard disk drive enablement
module (one to five hard disk drives) or the LSI MegaRAID SAS adapter is installed.
If these actions do not correct the problem, run the diagnostic program Lenovo Solution Center. See
"Lenovo Solution Center" on page 84. If you need technical assistance, see Chapter 12 "Getting information,
help, and service" on page 149.
"No Operating System Found" message or the system not starting from the correct
hard disk drive
Symptom: "No Operating System Found" message or the system not starting from the correct hard disk drive
Actions:
• Ensure that all hard disk drive signal cables and power cables are connected correctly. Refer to
"Replacing the hard disk drive" on page 110.
• Ensure that the hard disk drive your computer starts from is listed as the first startup device in the Setup
Utility program. Refer to "Selecting a startup device" on page 64.
Note: In rare cases, the hard disk drive with the operating system might get corrupted or damaged. In such
cases, you might need to replace the hard disk drive. Refer to "Replacing the hard disk drive" on page 110.
.
Chapter 8 Troubleshooting and diagnostics
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