Trying to add a PC3200 512 mb DDR memory to a Dell Dimension 3000 and will not work. I get 4 beeps followed by 2 beeps from machine.  What is the problem?  Thanks

   I would say to call Dell and ask them.
   If you had access to the beep codes (I think that each manufacturer's are different), that may help you figure out what is wrong.  Sometimes they are listed on the computer's manufacturer's website.
   Just guessing, I would say that it could be a bad memory card, it could be that your computer is limited in the amount of memory it can have and you are exceeding that limit, it could be that the card is not compatible with your computer, it could be that your computer requires the first slot to have a card in it and it doesn't have one there.  You could try putting the card in a different slot and see if that works.
   Always be careful in handling the card that you are always grounded (that one hand is touching the metal frame of your computer) and that you avoid touching the contacts because memory cards can easily be ruined by static.

Also.....installing the correct BIOS level has much to do with memory DIMM compatibility.  The memory manufacturer would be able to tell you what BIOS level is correct for the memory card and your DELL hardware.  Lots of this compatibility info can be found online at the manufacturer's web site. You may have to reinstall your old memory to download and 'burn' in (to ROM) any new BIOS.