Power-On Self Test - IBM PC 300 Maintenance Service Manual

Power-On Self Test

Each time you power-on the system, the power-on self test (POST) is initiated. Several items are tested during POST, but is
for the most part transparent to the user.
POST checks the following:
To 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 Utility
menu 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 the
error message or code with a beep. Depending on the criticality of the POST error, the system may halt and/or display
the 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 loading
of DOS or other operating system from diskette drive A or a hard disk drive or CD-ROM drive, depending on the options
selected in the Setup Utility.
If any errors are detected by POST, there will be an error message accompanied with an error code shown on display
screen and a beep. See "Index of Symptoms, Messages, Error Codes, or Beeps" on page 57 to find the most likely cause
and countermeasure.
System Board
Memory
SVGA Controller
Hard Disk Drive(s)
Floppy Diskette Drive(s)
Keyboard
Mouse
Parallel Port(s)
Serial Port(s)
CD-ROM Drive(s)
Sound Controller
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