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Subject: Re: What resets the motherboard?
Date: Sat, 09 Nov 2002 11:20:04 GMT
NNTP-Posting-Date: Sat, 09 Nov 2002 06:20:04 EST
Organization: Road Runner
You may be seeing the results of bad capacitors on the MB. There are
numerous reports on this, and the fix is to replace the caps. You can
check to see if this may be the problem by looking for caps that are 8mm
or less in diameter. Very often, these caps are leaking dielectric fluid
that corrodes the board. I usually can spot the ones going bad by giving
them a whiff. You will know the bad ones when you smell them!
A E wrote:
> Before I start reading up on every chipset out there, what circuit is
> responsible for power up reset on a PC? In the good old days of the C64,
> there was a 556 monostable that generated a ~1 second reset pulse on
> power up or reset.
> More and more people, myself included, are having strange intermittent
> reset failures in that the PC doesn't go past the memory self test, but
> a hard reset gets it going again.
> Yes, I've seen the designs with the relay that closes the reset switch
> longer, I'm not interested in that.
> There has to be a simple explanation. I don't know about the power
> supply theory, since there isn't much in my PC, yet it still has the
> Could a simple cap be drifting and changing a RC time constant
> Anyways, I guess in the meantime I'll research chipset datasheets.