Dell OptiPlex 755 - Manual (Page 245)

Bus type SATA 1.0a and 2.0;
USB 2.0
Bus speed SATA: 1.5 and 3.0 Gbps;
USB: 480 Mbps
Drives
Internal/External one D-module bay for an optical drive, second hard
drive, or floppy drive
one bay for a 3.5-inch hard drive
Connectors
External connectors:
Serial 9-pin connector; 16550C-compatible
Parallel 25-pin connector (bidirectional)
Video 28-pin DVI connector
Network adapter RJ45 connector
USB two front-panel and five back panel USB 2.0–
compliant connectors
Audio two back panel connectors for line-in and line-out;
two front-panel connectors for headphones and
microphone
System board connectors:
SATA 7-pin connector
Fan one 3-pin and two 5-pin connectors
Key Combinations
in Microsoft® Windows® XP, brings up the Windows
Security window; in MS-DOS® mode, restarts
(reboots) the computer
or starts embedded system setup (during system start-
up only)
automatically starts the computer from the network
environment specified by the remote boot
environment (PXE) rather than from one of the
devices in the system setup Boot Sequence option
(during start-up only)
or displays a boot device menu that allows the user to
enter a device for a single boot (during system start-
up only) as well as options to run hard drive and
system diagnostics
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 a sleep mode;
solid green indicates the power-on state.
amber light — Blinking amber indicates a problem
with an installed device; solid amber indicates an
internal power problem (See
Power Problems .)
Power supply status light green light — Solid green indicates the power
adapter is connected to an AC outlet and the
computer.
amber light — Solid amber indicates the power
adapter is connected to an AC outlet but not the
computer.
hard drive access light green
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 back panel (See Diagnostic Lights .)
Standby power light AUX_PWR on the system board