JP> I use a 386-20 with DOS 3.3 and PC-WRITE (ED.EXE) for all my 
JP>text work.
JP>  Problem:For the past few months,I had an error on bootup,with
JP>two beeps, "XCMOS CHECKSUM FAILURE and RUN SETUP UTILITY-PRESS F1"
JP> TO CONTINUE".I press F1 and the boot would sucessfully complete.
JP>At startup,the PC would go through the 8 MBs ram OK.,
 
JP>At random times,my 386 would freeze.It seems to
JP>tie in a keystroke on the keyboard and the 
JP>monochrome screen would flicker.If I'm in PC-WRITE,I could
JP>continue edited and moving text but when I tried to copy to the 
JP>harddisk,the system would freeze and I would have to power off/on.
 
  I lost the responses to my original query so I'm improvising.
After checking the hard disk and the power supply ,I decided to 
change the graphics card.This card was a special Card that allowed
EGA grapgics on a monchrome monitor.I replaced it with the original
long monographic card and it worked.No problems with freezing up.
I'll now have to check the shorting plug for Mono/Color on the 
motherboard.
 
I tried to salvage the EGA board by placing a heat lamp about 4"
above the bottom of the board and let it cook.When I could smell 
the bakelite,I figured that any cold solder joints would be 
corrected.
  I put the board back into the 386 .It was better but I still
had freezeups.So I put the long original mono board back in
and it's been working file since.
 
I still needed a backup for my DOS system.
Down at the Goodwill,I got a Gateway 2000 for $10.It had 
a 486-DX66 CPU with a 145 Watt power supply,8 MB RAM,341 MB hard 
disk,a 3 1/2" floppy,a slow modem,a VGA color card and DOS 6.22.
This was a motherboard where the added cards went in sideways.
 
 I had to get a used keyboard with a small connector ,like the
mouse for $2.Then tested the 486 with a spare color monitor.
It worked fine but the previous owner was security conscious
and put a password on the BIOS readout.Then I found that
on the motherboard,a shorting plug would remove the password
protect.
 
  I tried to hook up a monochrome monitor and the plugs
wouldn't fit.I didn't know that the plugs were different sizes.
So I put in my EGA board from the 386 and it worked fine.I had
to wiggle the  plug connection several times but it worked.
Maybe that was the trouble I had when it was in the 386.
 
 I used a DOS program PRUNE12.ZIP, to delete the windows files
and I was surprised how fast it worked.
 
Now I can transfer backups from my 386 to the DOS 486 using
floppies and zipped files.
At age 78,I learned something new.
 
 
 
 
 
 
 
 
It was set for Win 3.1 
 
 

--- Maximus 2.02