“uprgrading” my mom’s computer and my great idea was to just take the hard drive out of her old one and add it to the new one.  New one, WD2500aaks drive.  Old one, seagate ATA.  Do I need to change the jumper settings for the WD to a master or is there just no mixing SATA and ATA?

the connectors are different if you are talking about the old pata drives.

if i undrerstand you you cant connect an old style drive to a sata cable ( easily )

you’ll probaly be able to connect it onto the cable of the cd/dvd drive assuming thats not also a sata.

you may need to fiddle with either the cd/dvd or old hard drive jumper though.

hope that helps

Define “fiddle”.  The existing drive is SATA and is connected and works fine.  The only ribbon cable for the ATA is attached to the CD-ROM and has one additional connector.  I have tried plugging the ribbon cable from the CD to the slave drive, but get an error msg while trying to  boot saying it can’t load the operating system.  Do I need to do something with the BIOS?  The WD drive says it has no settings for slave/master.  The slave setting for the old hard drive is no jumper.  Tried no jumper and also tried limited.