POST may also display numeric or text errors indicating the nature of a hardware
problem. Numeric error codes are somewhat standardized into certain
code ranges. For instance, an error code in the range 100–199 indicates a motherboard
error, 200–299 indicates a RAM error, and 300–399 indicates a keyboard
error.
Text errors tend to be fairly direct statements, such as “Floppy drive failure”
or “Keyboard error or no keyboard present,” that display on your monitor and
usually require you to press a key such as F1 to continue.
Some hardware problems prevent any POST errors fromproperly appearing
on the display screen or coming through the system speaker. In these cases, a
special hardware tool called a POST card comes in handy.