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From: daved@micropro.UUCP (Dave Duchesneau)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Help! What is a 'system error 131' on an IBM PC?
Message-ID: <325@micropro.UUCP>
Date: Thu, 20-Nov-86 19:46:09 EST
Article-I.D.: micropro.325
Posted: Thu Nov 20 19:46:09 1986
Date-Received: Thu, 20-Nov-86 23:46:31 EST
References: <1068@zen.BERKELEY.EDU>
Reply-To: daved@micropro.UUCP (Dave Duchesneau)
Distribution: na
Organization: MicroPro Int'l Corp., San Rafael, CA
Lines: 34
Summary: 131 is a fubar cassette port. Usually.

In article <1068@zen.BERKELEY.EDU> c9c-ae@buddy.Berkeley.EDU.UUCP (Clayton Yee) writes:
>   I have been getting a system error 131 upon cold booting my machine,
>a PC-1 with a color graphics card and a multifunction card.  I have also
>had a few parity 1 and parity 2 errors.  Can anyone tell me what's wrong?


The 131 error is a system board error indicating a problem with the
cassette interface. It should be safe to ignore.
PARITY CHECK 1  means the _hardware_ detected a parity error in the
                RAM _on_the_system_board_.
PARITY CHECK 2  means the hardware detected a similar fault in the
                RAM located on any expansion memory boards.

It's marginally possible that all these problems are being caused by a
flakey DMA chip, which is the big one (same shape as the 8088) that
plugs in near to the power supply, in _front_ of the 8088/8087 sockets.
It's location U35 on the PC board, and is an 8237A-5 chip. It's the
single most common chip failure I've encountered in the old PC-1's,
in fact, it's the only consistent one I've heard of. If all else fails,
it may be worth replacing this chip (for around $30) before sending the
whole board off for work (for lots more than $30).

If you can, test your RAM in someone else's system. When you get BOTH
PARITY CHECK 1 _and_ 2, chances are it's not _really_ your RAM
that's having problems. That'd be sort of like having both rear tires on
your car blow out at once -- unlikely.

Good luck!


-- 

Dave Duchesneau
UUCP:  {hplabs|dual|glacier|lll-crg}!well!micropro!daved