I have been visiting a couple nes sites and I have seen people posting about NES carts erasing themselves over time. Can someone explain ?

Nothing last forever, but i have never experienced or heard of anyone who had have this problem yet.
How do they know its been erased? It might be other things, like dirt, that makes the game not work.

It's possible to have a defective nes cart when it was bought, but it's very rare for a nes rom chip to go bad.  If fact, I have never personally seen a bad rom chip for a nes game.


Is it possible you are reading conversations about prototype cartridges?  Prototype cartridges don't use roms to store the games.  They use eproms.  Erpoms have a limited life cycle and will lose their memory somewhere down the line.  

Regular games will be fine for probably long past your life time.  I am sure like Michael said you probably read something about protos.  The should start slowly erasing themselves after about 20-25 years.  The information will slowly decay away, and you are then left with a basically worthless piece of plactic unless you have the proto dumped so you can make a new chips for it.  This is why I don't collect protos, to much hassle.  I have 4, and think I may sale or trade those off for something soon.
~~NGD

Thanks for explaining

I read that NWC uses EPROMs also.  Can anybody verify this?

They do indeed us Eproms. :-/  They will be erased within the next 10 years for sure.
~~NGD

Yuppers, and lots of test carts, and actually lots of unlicensed games (like a lot of the color dreams).

Would it be "against the rules" (so to speak) to dump a prototype to a ROM just in case it ever loses its information?  Then if the proto loses its info, just write the ROM back onto new EPROMs and solder them on?  Or does that completely ruin the value?

Sorry if this question seems really stupid but I'm not a prototype collector.

I think this is a good idea and the only way to preserve protos. Everybody should dump the ROMs and save them on a CD or whatever. After the original chip lost his data, a new on can be produced and the proto should contain most of its value when the original chip is sold together with the repaired game.

I think it is also a good idea to do that, but I am not a proto collector either.  I think it would be pretty hard to really even tell the difference to be honest (might be wrong on that).  I don't think that protos will really loose there value so long as they keep working.  Some of the unlicensed games are not dumpable, especially unlicensed unreleased games that use a special board, like Airball does :-/
~~NGD

Well, they're all dumpable, games like airball are just unusable without that special hardware (no emulation is possible without emulating the special hardware and it's impossible to make a repro without reproducing the hardware).  It's still worth dumping for a backup to redo the eproms.  It is probably easier on a game like airball to remove the eproms and dump them directly.

As for "against the rules":  Yes, dump it.  If it's never been dumped, dump it privately and don't spread it around if you're afraid of the value going down.  You can usually refresh eproms and get more life out of them (erase and rewrite them, but you usually have to unsolder the chips if they're soldered in so it's a pain).  You usually need something like a copynes to dump the games unless you want to take the eproms off and use an eprom programmer (again often needs unsoldering for the eprom programmer part).  

If an eprom goes completely bad, replace it with another eprom (if you have a dump!).  As long as you get an eprom that doesn't raise any red flags, nobody will even know.

If anybody wants their game dumped privately, I'll be happy to do it if you pay the shipping both ways.  If the eproms are socketed, I'll be happy to refresh your eproms for free.

my Ninja Ryunken II erased itself after 2 years .... and several consoles can't read it no more ... and I didn't do anything to the cart .... it just stood there ...  :-?

I don't know if you're talking about a Proto or a regular cart, Nintendo. If you're talking about a proto, yes it can loose it's memory just by sitting there.  

 If you're talking about a regular cart, there's a difference between being erased and stopped working.  Most carts that stop working still have perfectly good rom chips (where the game is stored).  If it's worth paying the shipping both ways, I'd be glad to take a look at your cart.

nope .,... a regular FAMICOM cart .... and neah , it ain't worth it :) ... plus it is ERASED !!! ;)

The problem that kills most of the regular carts are the capacitors or resistors used on the board.

well my cart is toasted ... especially the condensators  :P