I just lost my save data on my copy of Dragon Warrior 3. Is this because the batter is no longer good? I read it with a meter and it's showing 3.08V which would seem to still be good. Might it be the capacitor on the board? Any help on this would be greatly appreciated. I'd hate to go through the trouble of changing the battery only to find this still happening. In 23 years of owning and playing NES games I have never lost a save before!

Man that sucks, I honestly wouldn't know what went wrong. Sorry I can't help here, maybe Martin knows.

It is possible that just reading the battery with a meter wouldn't pick up a voltage drop that might cause data to be lost.  Batteries are funny things - they can read fine with a meter but then you put it under load and the whole thing goes south.

20 years is a long time for any battery.

On another track - once when I was a kid (because I was stupid) I tried to get Zelda out of the deck with the game still playing and somehow it zapped my savegame in the process.  So I suppose a bad cart/deck connection might also have a hand in your problem.

You know what I tried the same thing with my Pokémon Gold for Game Boy Color. It was because I connected a wrong power supply to the GBC. Later the battery save was fine again but I lost my previous data. But I guess it is the battery in your case coz 20 years is a lot of time. Try changing the battery. It will need to be changed soon anyway.

I've written a tutorial for changing out the batteries on an NES cart and replacing them with a battery holder. It comes complete with pictures. Where could I post something like this so others could use it? Its a word doc so unfortunately gamefaqs is out. Any other suggestions?

Captain N wrote on 22. Aug 2009 at 01:33:

I've written a tutorial for changing out the batteries on an NES cart and replacing them with a battery holder. It comes complete with pictures. Where could I post something like this so others could use it? Its a word doc so unfortunately gamefaqs is out. Any other suggestions?

Yes, this information would be very beneficial.

shaggy wrote on 23. Aug 2009 at 03:09:

Captain N wrote on 22. Aug 2009 at 01:33: I've written a tutorial for changing out the batteries on an NES cart and replacing them with a battery holder. It comes complete with pictures. Where could I post something like this so others could use it? Its a word doc so unfortunately gamefaqs is out. Any other suggestions?   Yes, this information would be very beneficial.

Do you know of somewhere where I could post it?

My tutorial is now uploaded and can be read at the following location:

http://wiki.nesdev.com/w/index.php/Battery_holder