Dell OptiPlex 7020 Owner's Manual page 56

Feature
Password clear jumper
RTC reset jumper
Internal speaker
Intruder connector
Power connector:
Mini-Tower, Small Form Factor
Table 26. Controls and Lights
Feature
Front of the computer:
Power button light
Drive activity light
Back of the computer:
Link integrity light on integrated network
adapter
Network activity light on integrated
network adapter
Power supply diagnostic light
56
Specification
one 2-pin connector
one 2-pin connector
one 5-pin connector
one 3-pin connector
one 8-pin, one 4-pin, one 6-pin,
connector
Specification
White light — Solid white light indicates power-on state;
blinking white light indicates sleep state of the
computer.
White light — Blinking white light indicates that the
computer is reading data from or writing data to the
hard drive.
Green — a good 10 Mbps connection exists between the
network and the computer.
Green — a good 100 Mbps connection exists between
the network and the computer.
Orange — a good 1000 Mbps connection exists between
the network and the computer.
Off (no light) — the computer is not detecting a physical
connection to the network.
Yellow light — A blinking yellow light indicates that
network activity is present.
Green light — The power supply is turned on and is
functional. The power cable must be connected to the
power connector (at the back of the computer) and the
electrical outlet.