DR1 and DR2 relied on the motherboard's (or KSU main board) capacitor to backup memory, it uses a green capacitor.
DR3 and DR5.x use the feature/software cassette sleeve's capacitors, black and two of them soldered on small circuit traces, to backup memory.
If you swap them out, observe static discharge protection when handling the board and use a proper soldering iron so you do not burn the circuit traces off the board. You will need a vacuum bulb or solder wick or some such way to remove the solder to extract the old caps. They are Farad sized, so be careful not to short them as they can produce some real heat (and of course shorting is not good for the capacitor's longevity, too).
Mark you polarity before removing the old caps.
I have not seen it, but I have heard that a few board revisions have an odd pin spacing, which if you have such a board, you will only be able to solder in one pin of the new caps and you will need to make a small jumper wire to bridge from the board to the remaining pin.