Date: Wed, 1 Apr 92 08:54:08 EST
From: DJ Delorie <dj AT ctron DOT com>
To: John_D DOT _Sybalsky DOT MV AT envos DOT xerox DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: 486 freezes reliably?
Status: O

> We've got a 486, ISA, IDE disk, 16Meg, running DOS 4.01 and no other memory
> manager.  AMI BIOS of 3/15/91, unknown motherboard.
> 
> Running any DJGPP thing freezes the machine, such that CRTL-ALT-DEL doesn't
> work -- I have to hit the reset button.
> 
> Running the gcc, it seems to write a driver file for cpp, then freezes.
> Running debug32 gets to paging in the stack space (the "s" in the upper right),
> then freezes similarly.

There have been cases of 486 motherboards being bad.  Here is some old mail:

1> The symptoms are that when he tries compiling, after a brief whir of the
1> disk, the machine locks-up completely.  If an invalid command line is given,
1> then it runs ok, and reports the error.  The same problem occurs if an
1> executable (go32+a.out) from my machine is run.
1> 
1> I've stripped everything out from config.sys/autoexec.bat (except the
1> environment variables), and it does the same.  We are both running DOS 5.0.
1> 
1> His configuration is: Sonal PC, 486dx running at 33MHz with 4Mb total memory
1> (640k + 3.4M extended).  It uses an AMI bios, dated 3/15/91 in the rom, which
1> reports itself as Rev. C on boot-up.  Unfortunately I don't know what mother-
1> board he has.


2> Hah! There *is* life on other planets! I thought I was alone in the universe with 
2> this locking problem of DJGPP.
2> 
2> DJ, do you remember when I asked you this lock up problem a while ago?
2> I changed the motherboard (chipset manufacturer) and you said: 
2> "Hhm, interesting that hardware could affect DJGPP". I had a chipset
2> called UD (something like that, perhaps, UData, or UDS). After I
2> changed the motherboard+chipset the problem was gone.

DJ
dj AT ctron DOT com
Life is a banana.