Undetermined problem
Check the power supply voltages. See “Power supply” on
page 29. If the voltages are correct, return here and
continue with the following steps.
1. Power-off the computer.
2. Remove or disconnect the following, if installed, one
at a time:
a. Non-IBM devices
b. External devices (modem, printer, or mouse)
c. Any adapters
d. Riser card
e. Memory modules
Before removing or replacing memory modules,
see “System board memory” on page 59.
f. Extended video memory
g. External Cache
h. External Cache RAM
i. Hard disk drive
j. Diskette drive
3. Power-on the computer to re-test the system.
4. Repeat steps 1 through 3 until you find the failing
device or adapter.
If all devices and adapters have been removed, and the
problem continues, replace the system board. See
“Replacing a system board” on page 47.
104 IBM PC 300/IntelliStation Vol 3 HMM