Introduction 1-5Front PanelYour computer’s front panel contains the following indi-cators and controls (see Figure 1-2):• The power button provides control of the system’salternating current (AC) input power. The push-button switch operates as follows:— When the computer is turned off, pressing thebutton turns on the computer.— When the computer is turned on, pressing thebutton turns off the computer. However, a low-voltage (standby) current is maintained from thepower supply to the switch. To completelyremove all power from the system, unplug theAC power cable from its source.For systems running Microsoft Windows 95 orWindows NT with the Dell AutoShutdown ser-vice operational, pressing the power buttoncauses the system to perform an orderly operat-ing system shutdown before turning off. (Formore information, see “Dell AutoShutdownService” in Chapter 2.)NOTE: A Display Power Management Signaling(DPMS) monitor does not begin warming up untilthe computer to which it is attached is turned on.Thus, some DPMS monitors may not display a videoimage until several seconds after you turn on yourcomputer.• The green power indicator lights up when the com-puter is receiving power.• The hard-disk drive access indicator lights up whena hard-disk drive is in use. (Drive access indicatorsfor diskette drives and tape drives are located on thefront of the drives.)• The reset button reboots (restarts) your system with-out your having to turn the power off and then onagain. Rebooting the system in this manner reducesstress on system components.Figure 1-2. Front PanelBack PanelYour computer’s back panel contains various ports andconnectors for attaching external devices and includes asecurity cable slot and padlock ring. These features aredescribed in the following subsections.Connecting External DevicesYou can connect various external devices, such as amouse and printer, to the input/output (I/O) ports andconnectors on the computer’s back panel. The systemBIOS detects the presence of most external devices whenyou boot or reboot your system. When connecting exter-nal devices to your computer, follow these guidelines:• Check the documentation that accompanied thedevice for specific installation and configurationinstructions.For example, most devices must be connected to aparticular I/O port or connector to operate properly.Also, external devices like a mouse or printer usuallyrequire you to load software files called device driversinto system memory before they will work. Thesesoftware drivers help the computer recognize theexternal device and direct its operation.Always attach external devices while your computer isturned off. Then turn on the computer before turningreset buttonhard-disk driveaccess indicatorpower buttonpower indicator
