jakdedert wrote:

"Choreboy" wrote in message
...
Neighbors have a computer that won't work after a lightning strike.
With the video cable connected, the monitor stays black and in the
standby mode. There are howls from the speakers, like feedback. With
the cable disconnected, the monitor will briefly show a notice that it's
not connected. There are no howls from the speakers although the mic
cable remains connected.

With the power off, I checked the pins of the monitor cable to see that
the grounding pins were grounded and the signal pins were not. One
grounding pin is open, so it seems certain that the monitor is damaged.

The next step would be to try another monitor to see if there's other
damage to the system. In case the computer's video card is damaged, can
a monitor be damaged by plugging in to it?

'Probably' not, but why not try plugging their monitor into your computer?
That's extremely unlikely to cause any damage. Then, I'd take *everything*
out of the neighbor's computer, except the vid card...unplug memory, all
drives including floppy...just leave in the CPU and vid card.

See if it boots up and asks for memory. If so, install that. Keep
going--adding one device at a time--until you find a problem device...skip
that one on the next go-round, until you've ID'd any and all such.

Rinse, lather, repeat.....

jak

Why is a monitor less likely to damage a computer? If the monitor
proves bad, as indicated by the open on a pin that should be grounded,
won't I still have to connect a good monitor to the neighbors' computer?

What might be wrong with a computer's video card that would damage a
monitor? I could check the video outputs with a scope. Would that
assure me that it was safe to plug in my monitor?

I thought I'd connect a good monitor and see if the computer worked.
What's the point of disconnecting everything in the computer without
first knowing that anything is wrong?