83Power-On Self TestEach time you power-on the system, the power-on self test (POST) is initiated. Several items are tested during POST, but isfor the most part transparent to the user.POST checks the following:• System Board • Mouse• Memory • Parallel Port(s)• SVGA Controller • Serial Port(s)• Hard Disk Drive(s) • CD-ROM Drive(s)• Floppy Diskette Drive(s) • Sound Controller• KeyboardTo start POST, turn on the monitor and then the system unit. The following will happen:1. The IBM logo will appear on center of the screen.2. At this time one of two hot-keys may be used. The F1 key, as described on screen, will cause the system Setup Utilitymenu to appear. The F9 key will switch the graphical IBM logo screen to the traditional text-based system startup screen,which displays BIOS version and system memory tested.3. If an error is detected during POST, the IBM logo screen will automatically switch to the text-based screen and display theerror message or code with a beep. Depending on the criticality of the POST error, the system may halt and/or displaythe message “Press F1 to go to the Setup or Enter to continue”.If this message appears, pressing the Enter key will allow the system to attempt to proceed despite the reported error;pressing F1 will cause the system Setup Utility menu to appear.4. If no keyboard keys are pressed, and if POST is completed without errors, the system will then proceed with the loadingof DOS or other operating system from diskette drive A or a hard disk drive or CD-ROM drive, depending on the optionsselected in the Setup Utility.If any errors are detected by POST, there will be an error message accompanied with an error code shown on displayscreen and a beep. See “Index of Symptoms, Messages, Error Codes, or Beeps” on page 57 to find the most likely causeand countermeasure.