Dead IBM PC 5150 motherboard - help troubleshooting

[Richard Beaudry]

Hello all and thanks for the suggestions...

Here's the story so far:

1) Power appears good -- measured correct voltages at power supply header on
motherboard, and at various chips on the motherboard.  All seem to be within
specs

2) "Power good" line stays at +5VDC -- I believe this is correct, and
signals that power is indeed good

3) Processor reset line -- at power up, briefly goes to +5VDC, then back to
0VDC and stays at 0VDC -- I don't think it is active low, so this should be
correct, right??

4) Triple-checked configuration switches, and they are correct for the
configuration

5) Clock input to 8088 is dead-on 4.77xxxxxx MHz (my scope shows all the
digits, but I don't remember them :-) -- I think the 4.77MHz is close
enough).

6) One thing that seems odd is that the ADxx (Address/Data) lines seem
"stuck".  The scope does not show a waveform, and measuring with a meter
shows some lines right at +5VDC, some at about +4VDC and some at 0VDC.
Perhaps the processor is indeed HALTed???

That's where I am right now ... I'll remeasure the ADxx lines, and post the
full list of values ....

Thanks again for all the suggestions!!!

Rich B.