Dell OptiPlex 755 - Manual (Page 135)

(during start-up only)
<F12> or <Ctrl><Alt><F8> displays a boot device menu that allows the user to
enter a device for a single boot (during start-up only)
as well as options to run hard drive and system
diagnostics
<Ctrl><p> displays the Management Engine BIOS Extension
settings screen that allows you to modify the settings
Controls and Lights
Power control push button
Power light green light — blinking green indicates sleep mode;
solid green indicates power-on state.
amber light — blinking amber indicates a problem
with an installed device; solid amber indicates an
internal power problem (See
Power Problems .)
hard drive access light green
Link light (on front of chassis) solid green light indicates network connection
Link integrity light (on integrated network adapter) green light for 10-Mb operation; orange light for 100-
Mb operation; yellow light for a 1000-Mb (1-Gb)
operation
Activity light (on integrated network adapter) yellow blinking light
Diagnostic lights four lights on the front panel (See Diagnostic Lights .)
Standby power light AUX_PWR on the system board
Power
DC power supply:
NOTE: Power consumption from an AC power source
can be zero when the computer is unplugged from
that power source. However, the computer draws a
minute amount of power from the internal coin cell
battery even when the computer is not drawing
power from the AC power source.
Wattage 305 W
Heat dissipation 1041 BTU/hr
NOTE: Heat dissipation is calculated based upon the
power supply rating.
Voltage manual selection power supplies—90 to 135 V at 60
Hz; 180 to 265 V at 50 Hz
Backup battery 3-V CR2032 lithium coin cell
Physical
Height 41.4 cm (16.3 inches)
Width 18.5 cm (7.3 inches)
Depth 43.9 cm (17.3 inches)
Weight 12.34 kg (27.2 lb)
Environmental
Temperature:
Operating 10° to 35°C (50° to 95°F)
Storage –40° to 65°C (–40° to 149°F)
Relative humidity 20% to 80% (noncondensing)
Maximum vibration:
Operating 0.25 G at 3 to 200 Hz at 0.5 octave/min
Storage 0.5 G at 3 to 200 Hz at 1 octave/min
Maximum shock:
Operating bottom half-sine pulse with a change in velocity of
50.8 cm/sec (20 inches/sec)
Storage 27-G faired square wave with a velocity change of
508 cm/sec (200 inches/sec)
Altitude: