Of course, there may be a number of things that have gone wrong, but 
there is a good chance that it is your motherboard battery.

Your computer is probably several years old now, and the battery on the 
motherboard may have worn out.  CMOS memory that stores your BIOS 
settings uses a very small amount of current that is supplied by the 
battery when the computer is powered down.  After three or four years 
that battery wears out and the CMOS settings are lost, with the BIOS 
reverting to their default values.  If the default location for the 
system disk does not eventually reach your hard drive (for example it 
first looks at the floppy and then the cd rom and then gives up), then 
it cannot find the system disc, i.e. the hard drive,  and  you receive 
that error message.

Most motherboard batteries are CRXXXX where XXXX is some number.  Look 
on the mb for the battery and find the number on it.  You can probably 
find a replacement for it at Radio Shack or Wal-Mart for between two and 
three dollars.

If you replace the battery, then you have to go into the BIOS settings 
and set the default locations for the boot order.  (Other settings may 
have been lost, too.)  If a new battery does not solve the problem, you 
are only out a couple of bucks, and you will have a new battery on the 
mb.

If you have a manual for your computer and/or motherboard, you can check 
and see what "one beep" represents.  It may, however, be misleading.

I am not sure what you mean by "Can't get into setup."  If Windows does 
not boot, you can't get into anything except the BIOS.  If you mean that 
you can't get into BIOS, then that is not a good sign.  However, if you 
get an invalid system disk message, then BIOS are surely working (more 
or less) and you should be able to access them.  You can look and see if 
the boot order is incorrect.  Change it and see if Windows boots 
properly.

HTH

Dean Kukral

----- Original Message ----- 
From: "Orrin Bendfelt" <[log in to unmask]>
Sent: Saturday, January 01, 2000 1:43 AM
Subject: [PCBUILD] Boot?


        Running XP SP2, pentium 4, 1G RAM
       Last shutdown was normal. Started today, get one beep then 
message saying "Invalid system
       disc".   There is no floppy in drive.  Reseated all connectors, 
video card and RAM.  Can`t get
       in to setup.

       Thanks for any suggestions.

       Orrin Bendfelt

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