Item Indicator, Button, or 
Connector
Icon Description
11 Optical drive (optional) One optional slim SATA DVD-ROM drive or DVD
+/-RW drive.
For information about the supported optical drive, 
see the Technical specifications section.
Front panel features of the 4 x 3.5-inch cabled hard drive system
Figure 3. Front panel features of the 4 x 3.5 inch cabled hard drive system
1. Power button 2. NMI button
3. System identification button 4. Video connector
5. Diagnostic indicators 6. USB port (2)
7. Information tag 8. Hard drives
9. Optical drive
Table 2. Front panel features of the 4 x 3.5-inch cabled hard drive system
Item Indicator, Button, or 
Connector
Icon Description
1 Power button
Press the power button to turn the system on or 
off. The indicator on the button indicates if the 
system is on or off.
NOTE: To gracefully shut down an ACPI-
compliant operating system, press the power 
button.
2 NMI button
Press the NMI button to troubleshoot software and 
device driver errors when running certain 
operating systems. Use the end of a paper clip to 
press the NMI button.
NOTE: Use the NMI button only if directed to 
do so by qualified support personnel or by the 
operating system documentation.
3 System identification 
button
Press the system ID button:
• To locate a particular system within a rack.
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