Diagnosing And Solving Problems - NEC POWERMATE P60D Service Manual

Table Section 4-4 describes the possible ISA NMI error messages.
Message
Memory Parity Error at xxxxx
Memory Parity Error at xxxxx
DMA Bus Time-out

Diagnosing and Solving Problems

One beep indicates that the computer has completed its power-on self-test. If intermittent
beeping occurs, power off the computer and try again. If the beeping persists, see
Table Section 4-4. The table summarizes problems that may develop during computer op-
eration and lists (in sequential order) suggested corrective actions.
Table Section 4-6 Problems and Solutions
Problem Symptom
No power Power lamp on computer status
panel will not light.
Table Section 4-4 ISA NMI Error Messages
Description
Memory failed. If the memory location can be determined, it is
displayed as xxxxx. If not, the message is Memory Parity
Error ????.
An expansion card failed. If the address can be determined, it
is displayed as xxxxx. If not, the message is I/O Card Parity
Error ????.
A device has driven the signal for more than 7.8 microseconds.
Maintenance and Troubleshooting
Solution
1. Check that the power cord is
plugged into the AC connector on the
computer.
Check that the other end of the cord
is plugged into a live properly
grounded AC power outlet.
2. Check cable connections between
power supply and system board.
3. Systematically eliminate possibly
shorted PCBs by removing cables and
expansion boards.
4. Check the +5 and +12 power supply
voltages (see Appendix A, Connector
Pin Assignments). Measure voltages
with the system board installed.
5. Replace power supply.
6. Replace system board.
4-7