Replace Your Game Cart Batteries (Without Losing Your Saves)!

Many older cartridge-based games use internal batteries to keep your game saves going. These batteries won't last forever though, so let's take a look at how you can replace these batteries without losing your saves in the process.
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[@teamtinyturtle9103]

It's like performing open heart surgery. It would be a very good idea to practice a few times using battery saves you don't necessarily care about before jumping in to replace the battery on the classic save you wish to preserve.

[@hellterminator]

I'd recommend putting a resistor in series with the temporary battery. Pretty much any resistor you have. 1k-100k would be ideal, but anything lower than 1M will do. The moment you connect the temporary battery, one of the batteries will start charging the other (usually the temporary battery will charge the discharged battery present), however these batteries are not rechargeable. Now, the internal resistance of the coin cell _should_ limit the current to a value low enough to not cause a catastrophic failure during the time you'll be working on it, but having an extra resistor (to further limit the current) won't hurt.

[@mooloa]

You just helped me save my Pokemon silver save. Thank you so much!!

[@ThisDoesNotCompute]

+Darcy McSketchy Awesome! Glad it worked out!

[@03mm24]

Sadly...I was too late 😟

[@ivaneduardochavezgutierrez4119]

Did you use the same AA battery holder as in the video for the temporary battery?

[@h8GW]

@ivaneduardochavezgutierrez4119 You can take wires with alligator clamps on one end and put magnets in the jaws to hold it to another coin cell. You could also use magnets to hold the bare ends of wires against the surrogate battery, but I trust that less to hold the connection, so try not to bump anything💀

[@KanyeWestLover12345]

how do you do this on gameboy?

[@Blinkation]

its like defusing a bomb

[@apptreeline]

Haim Bilia bomb has been defused

[@EconomySpore]

App Treeline Counter-Terrorist's win.

[@opticishere1490]

Kaneda lmao

[@Ristarite]

MISSION FAILED

[@ErtugrulOzdemir-mf1gl]

@@Ristarite LMAO

[@Internetspaceships]

Nice video! I just recently changed out a battery on a N64 Zelda Ocarina of Time Cartridge. I did not however buy those batteries with tabs. What i did was i bought a whole bunch of 2032 Coin Cell holders on dealextreme and soldered one of those in place that makes switching batteries much easier in the future. Seeing the amount of free space inside the SNES cartridge i had an idea of hooking like 3 of those Coin Cell holders together in parallel and sticking them in the top part of the cartridge. That way you have like 30years of battery and can hotswap batteries whenever without losing power.

[@ThisDoesNotCompute]

+Internetspaceships Swapping in a coin cell holder is a good option for some carts, but for others (like Game Boy carts) there just isn't enough room inside. Thanks for watching!

[@SianaGearz]

It's possible even if there doesn't seem to be enough room! There are numerous kinds of battery holders. There's the sewable battery holder which takes a lot less space in one direction. There's also an SMD battery holder that doesn't add barely any bulk from any side! Unfortunately on one side, its connection to the board needs to be improvised, and on the other, a separate nickel or chrome strip must be fashioned to contact the minus side of the coin cell. Finally there are all manner of brackets that become battery holders once soldered in, but they are not widely available. Games with RTC may really benefit from a battery holder. However, one should then also provide the alternative power terminal as well, if installing the holder. Maybe just as a couple of old resistor legs along the board that one can crocodile clip onto, and some isolation so that it may not go too wrong? Another disadvantage of any holder is that mechanically, the battery can be displaced due to impact and lose contact. So this was probably the reason why no holder was installed in the first place, as the simple metal bracket types would have been easier to install at manufacture, because thermal cell damage could be excluded.

[@SianaGearz]

Waaaaait, once you have a holder, you don't necessarily need a power terminal. You simply dismantle the cartridge, plug it bare naked into the console, and replace the battery while the console is running. But check first, SRAM should be supported by system voltage, which is either connected to SRAM directly but the battery has a diode in series with it to avoid charging, or there's a power management circuit which disconnects the battery from SRAM when there's system power. Also i had another thought just now, it might be a good idea to write down the year on the battery that you put in or on the holder, wherever visible, so you're not tempted to replace it too early and too often.

[@trindalas]

I was thinking about whether that would be possible myself. I’m not really someone who likes to solder so that would be ideal for me. But I also have a LOT of game carts and that would take me ages to get them all replaced... probably expensive too 🥺

[@megamariofan4009]

Where did you find the points where the battery sent voltage to, on Zelda OOT

[@milesaway1980]

Thanks for the video. I just found my old NES in the garage (hadn't been turned on for probably two decades). Powered up Zelda and Final Fantasy, and the saves are still there! These batteries are probably 35 years old! It'll be awesome to swap the batteries out without losing them.

[@coolestto]

That's pretty smart! Never would have thought of that, everything I've seen before is for Gameboy cartridges, where people have them plugged into a DS to keep power to it while the replace the battery.

[@aaronspacee]

You can achieve the same effect by replacing the battery while the game is in and running, the save file will vanish when the battery is removed, but your game will still be where it was, and when the new battery is in, save the game

[@animeannaotaku]

How will this work when you have multiple save files, such as on Zelda Ocarina of time?

[@RandomizationShow]

Anime Anna Guess you’d have to choose the most important one to you

[@pinkcigarette]

What do you mean by "while the game is in and running", do you mean having the back panel of the cartridge off while the game is in the console

[@clark4041]

This guy lives on the edge :p

[@ssokolow]

Or just buy a cartridge dumper that supports dumping and restoring game saves for the relevant consoles. It's like that DexDrive or MaxDrive you might have from back in the day, but for in-cartridge save data. Much simpler and less risky.

[@bobskie321]

Who came here after it's too late?

[@nine-ig1xq]

bobskie321 8 years too late for me

[@opticishere1490]

nine Same lol

[@dominicsevilla1189]

I just want to be able to save. My gba silver gsme is currupted

[@matthewbryant2972]

right here... final fantasy legends III and Ogre Battle gone... what about a forensic data backup? Like in the movie Molly's Game?

[@asdfpoop33921]

I came here when I realized my new cartridges don't save shit.

[@ChrisFredriksson]

What a smart idea, haven't thought about that before! If, or well.. when I change the batteries I will probably skip the "saves".. They don't really mean a lot when I'm not playing the games so often. I'm more of a collector than player, when it comes to the old games. But if I do want to save the saves and the battery isn't dead already, this would be a really great thing to do =) Great video Colin!

[@zentekvideogames3589]

I'd suggest using a Retron 5 where you can dump your save files before performing this process. If you do mess up and erase your game while changing the battery, you can still save back your old save file to the cartridge through the retron after you have placed the new battery.

[@BigHead2615]

I mean, I gave you a like because, your video here is the first where I think I can learn to solder without fear of ruining or destroying one of my games. To me, losing save files is the least of my worries, part of my love for continuing to play all my NES, SNES and Genesis games after all these years, is starting over and re-experiencing the games all over again. I get that there are people that care about their very first, original save file that they made as a kid on A Link To The Past or Kirby's Adventure, but yeah, this is the first video I've found (was recommended to me actually), where hands and fingers did NOT get in the way of seeing how to actually solder. I just got Chrono Trigger and Super Mario RPG, both CIB just this month, and I actually decided to replace the battery in SMRPG because, a) I wanted to wipe the existing save files, so that I had the feeling of owning a new copy of the game, and b) because I'd rather there be a new battery in the game, rather than the same one it came with in 1996. All I have to say is, my hands were shaking, and I was terrified I was going to fry the game or something (I had a soldering iron and solder this time around, otherwise I've replaced batteries before by using electrical tape to keep the new batteries in the connectors), and I decided against learning now with a game I cared about very much, and just used electrical tape to keep the new battery in.

[@Der_Kleine_Mann]

It worked, yesss💪 I'm so happy that my old game saves are not lost.

[@but531]

My man you are a genius , you can't imagine how really sad i was so many years now, because i couldn't imagine how can i change a battery in these old consoles games without loose the saves. It was a really pain for me because i am a fun of the old video games , but i am not an extreme player to finish a game quick without the need to save a game. As you understand i need long time to finish some games, because i can't finish a game with one continuous playing, like this very very fucking tough game for me the Megaman x3 SNES, that i couldn't finish it, without the save feature in New 3ds. And now after many many years, it's the first time in my life, that i see a way, HOW TO DON'T LOOSE THE SAVE of a game when change a battery in an original game . So that's mean i will spread in this fucking universe, this awesome solution video. My man you are awesome, because you share this awesome solution. Also if you can, make more videos of how change the battery from the other consoles, like Game boy consoles or Sega or anything you can. We will appreciate it the funs of the retro games, seriously we do.

[@devikwolf]

For Game Boy games, one option is using the InterAct "Mega Memory Card," which will let you download the savefiles from your carts and restore them later. They can still be found for under $20 without much hunting. I've had the same one for nearly 20 years and it hasn't failed me once. Plus, my original Pokemon Red and Blue saves from '99 are there alongside my most recent backups of the same saves, 19 years later.

[@StephenArsenault]

Dang, Colin. Didn't realize how long you've been making informative videos! 👍

[@nickmoniz400]

Never heard of this method, but a fantastic one at that. I use a Super UFO Pro 8 which lets me copy the sram (save file) of my snes games to an SD card, after replacing the battery you can load the save back onto the cartridge. But this looks like a much more cost effective option, because the super ufo costs around 50 bucks. Fantastic video as always, keep it up!

[@Skidonti]

Thanks a lot Colin! I hadn't thought of this being possible but, of course, it makes complete sense!

[@Michaelwave64]

This is going to be my first soldering project. Thanks for the help.

[@rashid411]

I seriously was about to click away xD Good one Colin.

[@mistaecco]

Just found your channel- really good stuff man! Subscribed for sure =D

[@watchingdanny]

Just the info I was looking for. Thank you.

[@clark4041]

I was just thinking this could work! Thank you so much for showing us retro fans what’s what :)

[@Der_Kleine_Mann]

That's exactly what I wanted to know, so thank you for showing. Hope I am able to do it like you showed on my old games, especially Super Mario World for SNES is where I really would die if the saved game would be lost.

[@mandarian87]

I'm absolutely not smart enough to do this on my own, however, I appreciate the advice. Great video, very informative, thanks.

[@aikoyanai5933]

XD

[@SlothyWoffy]

New sub pal, really enjoy your videos :)

[@user-ps4gv7ge6t]

*Mission Impossible theme plays*: Me while trying this.

[@mexicool187]

There where only 3 things I learned in high school one was how to solder. great video.

[@lethe9572]

For Gameboy games the way you replace the battery is slightly different, but overall, it's the same. Thank you for this video! It will be very useful.

[@SumDumGy]

Thanks for being awesome!

[@rerolledDK]

I used a similar technique when I replaced my batteries several years ago. My Chrono Trigger and Final Fantasy III saves survived the process. Breath of Fire II and Secret of Mana saves did not survive, but those two carts had lost saves in the past - long before the battery needed replacing.

[@shadowform952]

I'm not sure about the consoles, but you can take the front case off of a gameboy cartridge, put it in your gameboy and turn it on, then replace the battery normally without losing your save.

[@TheChromaKid]

+Commissar Barry yep. I've no experience with this sort of stuff so I'm gonna do that for my pokemon blue. Thankfully, I started off with the GBA pokemon games as a kid, And only recently played blue/red. So I'm only sentimental with my GBA and DS pokemon games. So my DS pokemon are safe and sound, And my gba ones just need to be transferred to my Ds games while I still have the originally battery working. And Also thankfully heartgold is my favourite, So I have no problem not being able to get my pokemon back to the gba cart.

[@markvickery5894]

TheChromaKid actually the gba only uses a battery for keeping track of time, the batteries don’t keep your save files. All 3 of my Pokémon gen 3 games have a dead battery but I still play them everyday. Only thing is I can’t get to the alternate half of shoal cave, can’t do the lottery, and can only evolve one of the gen 2 Eeveelutions, plus I’m sure there is other stuff, but I can still play the game other than that

[@HappyBeezerStudios]

In a GBA original GB/GBC cartriges are poking out, giving you access to the backside with the soldering tabs. But with games in their fitting Game Boys thats a bit more troublesome

[@FireheartSamurai]

Mark Vickery That actually happened to my Pokémon Emerald game that I got back in middle school from a person. I also can’t do the other half of Shoal Cave, grow berries, breed Pokémon, & other time based events to.

[@MMSPRODUCTIONZz]

Nice video ! Thanks again

[@TheChromaKid]

Nice video as usual! Thanks. Been meaning to do this with some of my pokemon games, But didn't to lose my charizard XD

[@TheChromaKid]

+TheChromaKid didn't want to*

[@WizardClipAudio]

Dude,... my friend who passed away years ago, his Pokémon game may just be saved!!!

[@demonofshadows9199]

let us know the results.....

[@WizardSquares]

Still waiting

[@deadalpeca8099]

Still waiting

[@ufkingwotm9260]

Still waiting

[@SHODAN-TriOptimum]

Wizard Clip Audio still waiting

[@shaynmckeon7779]

Thanks, I had this same idea and its good to have confirmation . I will be attempting this on a sega genesis sonic the hedgehog 3 cartridge. Although I have not opened it up yet I figured it would have the battery save feature.

[@Mrcheesestk]

Retron 5 lets you transfers game saves from the cart to the console or an SD card and then back to the cart again - saved the lives of my Pokémon games

[@jaymesjmathias9390]

You're The Man!!! (That is meant to be and always will be a Positive Compliment in my neck of the woods:-)

[@RetroPlayer93]

Amazing video! I'll be able to keep my zelda saves now! Thank you!

[@ramonhuerta6172]

Amazing share! Thx!

[@trandinhvietdung9357]

0:00 - 0:58 nice joke Colin :D great to see your channel growing and thanks for good content

[@markwmbrown]

Nice! Not good at all with tinkering work electronics. At least I know it's a battery in my new cartridge, hopefully there is a good game repair shop around me. Thanks for video

[@kahlil88mph]

Just modded several games last night with battery holders, but I was stupid and didn't watch this video first for the temp battery trick!

[@TheIdleCrow]

It's always depressing when the batteries die, & all those old saves from my childhood are gone.... It's a good idea tho what you got! I should really get the willpower to open up all my old favorite games, & check what batteries are within them, & begin replacing them....

[@michaeljohnson1443]

Awesome. Thank you. :)

[@javierortiz82]

I always thought if this was possible, good to know it can be done this way. How about adding battery holders for easier battery changes in the future?

[@beatchef]

Batteries tend to last 30+ years and batteries tend to pop out or generally come loose from holders

[@m1k3l1f3]

Got a Super Mario Deluxe cart that needs a new battery. This video will help out lots.

[@megasilverx1268]

Thank you! Your video was helpful. Now I can play Mario's Super Picross with a working battery :)

[@thomasgonzalez8985]

Excelente, la otra vez vi un video en el cual si haces el reemplazo de la pila en el lapso de 1 minuto aprox, aún podías tener tus avances porque explicó algo sobre que los componentes seguían energizados y eso hacía que la nueva pila quedara con ese último grabado sin problema.

[@lssjgaming1599]

This is cool for keeping your 100% save files

[@rodrigomolinsky]

I really laughed at the end of the first minute!

[@jaysonbosshog6934]

Thank ur ou for your help sir! All my pokemon are saved!

[@TheChiperSdre34]

You can also buy a Mega Memory Card and back up tons of saves to that. You can go even further and dump those saves to a flash cart, then dump them to your PC. Then, when your battery dies, just replace it and redownload the save.

[@joeschmo5171]

Thanks for the info! I was always curious if this was possible, but had always worried that doing this would provide too much voltage. Now I know better!

[@playmooregames371]

Awesome video! If you have a chance, could you make a tutorial for changing a Wonderswan cartridge battery?

[@hullinstruments]

Also, does almost 7 volts not damage the memory? Sorry for the newb questions

[@joaquin6726]

You're not alone, I have exactly the same question.

[@cbk12]

Wondering same

[@owaing]

@@cbk12 No, a second battery in parallel doesn't increase the voltage. It's still 3V. Two batteries in series would increase the voltage.

[@cbk12]

@@owaing sorry for being lost a little whats difference between parrellel and series. Thanks in adv

[@owaing]

@@cbk12 Series is one after each other in a long line. In parallel the path is divided so that each one is used together as one. en.wikipedia.org/wiki/Series_and_parallel_circuits The examples in this show resistors, but the principle is the same for batteries.

[@Gl4uc0n]

I saved my friend's Pokemon Crystal save from childhood, except I put it in a Gameboy SP and powered it on while I replaced the battery. Wish I'd have seen this video before I did that, it was one of the most nerve-wracking repairs I've done because I was risking his childhood save and he insisted we used his Gameboy, so I had almost no liability should I have messed up. It worked, but in the future, I'm definitely going to do this instead.

[@joques7373]

Cool video! I have a question that I've been trying to google, but having no luck: Do you know at which battery voltage these volatile save chips will lose their save? I can fumble my way around with a voltmeter, but can't solder - and so I kinda need to know at which point I have to impose on a certain friend of mine who does solder.

[@cgimovieman]

I still have my original SNES from 1991, and 5 of my very favorite games from the same time. My original saved games from this time are still on the games and working, but I’ve been concerned about the carts in recent years. Less about losing those original games though and more about the batteries bursting and ruining the carts entirely. So I’ve considered doing this. I’m very sentimental about my SNES though, and have been nervous about cracking open any of the games or the console itself, as they’re all in absolute mint condition. Even as a kid, I never touched the labels on my games when I handled them either, for fear of the oils on my fingers damaging them, and very carefully inserted the games with two hands. But I probably should be doing this now. I’d also like to Retrobright the lower half of my SNES console too, as even being kept in a controlled environment and original plastic, it has still yellowed. But again, disassembling it and wrapping the plastic in goo? 😬 It makes me so nervous. I know it’s just a gaming console, but the period of years from what that system came out until maybe 5-6 years after we’re maybe my very favorite time and memories from growing up.

[@henryglends]

What you could do is buy a cartridge dumper, then put the saves back onto the cart using that same dumper, and replace the battery a lot easier!

[@cgimovieman]

@@henryglends Thanks for the tip. I’ve also seen some videos showing how to temporarily solder two electric leads to a power connection while you replace the battery. Whatever method, I’m less concerned I guess with losing my old saves, and more concerned about the cartridges not being damaged because the old battery bursts.

[@INeverWanted2010]

RIP my original Pokémon Red file.

[@wildgoosespeeder]

For Game Boy and Game Boy Color games, there exists an accessory by InterAct, well known for their GameShark line and now a defunct company, called the Mega Memory Card. I think it uses flash memory to store backup saves of games by reading the battery backup save of the attached cartridge and making a copy of it for future use. An issue with it is with Generation II Pokémon games, the time of day will be inaccurate when the save is restored, but I think a reset button combination exists to trigger the time to be blanked or something.

[@Kniffel101]

+wildgoosespeeder Nice! :) And a tip for Gen III users (even though they use a flash chip and gamesaves are save, anyway): If you own a Nintendo DS with a GBA-Slot and a Flashcard there's homebrew software to dump ROMs and saves that can be used with literally any emulator! (It's called "Rudolph's Backup Tool" or sth like that)

[@BobTheStrangeMan]

Couldnt you technically just put it inside the console and power it on and then desolder it while the game is running or is the battery vital, because I noticed when my pokemon crystal batty died it would still be able save as long as it remained in the gameboy. Just a thought

[@Kalvinjj]

Indeed, you can do exactly this, since there's a chip inside the cartridge that changes between the battery and internal power while it's running, so the battery "unplugged" while the console is on. For a Game Boy game it might be cumbersome, tho using a GBA would help that task (not on GBA games whoever...). Whoever slipping your hand on the soldering iron might make things a lot worse than if it was unplugged, so it's a risk to take.

[@h8GW]

With the amount of empty space in most cartridges, I'd probably install 2-AA holder and swap _those_ cells out when needed.

[@DavideRnd]

Your guide is very interesting, I want to know if your method works with Nintendo 64 Controller Pack, without losing saves, thanks.

[@violettangie1560]

Just ordered my fluke 179 just for this

[@interlinkedMedia]

Great video. How does one check the polarity with the multi-meter?

[@cbk12]

Wondering the same

[@alexnava8729]

Today I was going through my closet and found my Pokémon silver cartridge from 2000, when I was 10. I thought about how cool it was when me and my friends would play together at school and have Pokémon battles. So I went to play and visit my old friends (in game Pokémon’s) from 20 years ago, and everything was gone.... all that hard work 😢 gone. Only memories left.

[@minorOffense]

What about making a cartridge slot holster that just gives power? Slide the cart in, powers through the cart pins, do you soldering and slide out the cart. Could be a good use of old connector ports on broken consoles.

[@kevinwoolford123]

I recently replaced all my save batteries in my nes games. I didn't do this technique. I replaced zelda 1 batt and lost the save. I replaced zelda 2 and it still had it!! How does this happen I thought the moment the battery is removed its all gone? Very odd lol

[@demonofshadows9199]

hello! how to know which are the points i need to attach the temp battery? only 2 points will have power on the back ?

[@udontneedtoremember4840]

Where did you get/what did you use to make the wired AA battery holder?

[@wildcard13294]

Gonna do this for Super Mario Bros. Deluxe (since most GBC carts are transparent I can see the battery) soon.

[@71dembonesTV]

I just pop the naked circuit board into the respective console and swap the battery with it running. The method shown here works too but I'd say its a bit more risky.

[@EddyRodz91]

Hi!! I saw your video and helps me a lot, but in my case was on my Pokemon Yellow cartridge. but I have Pokemon G/S/C and I need to change the batteries but I don't know where I can solder a temporary battery. Can you help me please?

[@hullinstruments]

I assume this would work when repairing old oscilloscopes and test gear????? I always run into old tech tektronix and HP test equipment that has leaky or dying batteries… And I’m afraid to change them because it could wipe the volatile memory or something like that. I guess this would work just fine? Thanks for the great content.

[@PuffyRainbowCloud]

If you don't mind losing the saves, such as if you've purchased a cartridge recently and the previous owners' data was on there, you can also replace the SRAM and battery with an EEPROM in many cases. Try searching around on the internet for solutions for your specific game!

[@Unexpectedstuff]

This is cool, But I usually put just a sockets for battery instead of using special 2032. (It's very useful with dreamcast battery which keeps the internal clock).

[@RETROCUTION]

Your comment is irrelevant to what is going on this video. He is showing how to add power from another source in parallel with the battery, so you don't lose your save when you remove it. This would still apply even if you added a socket.

[@lavenderhawk]

need a n64 cartridge video!

[@TesserLink]

what are the odds i was just about to try and do this to a GBC game today.

[@speedpunxclub7550]

Does this work for N64 controller paks ( Memory cards) as well? Also does it matter where the back up battery packs ties in, or too any pos / neg , 3 v pin on the game card?

[@jeremylovesretro]

In choosing two points to connect the temporary battery to, am I just looking for them to read approximately 3V on my multimeter while the original battery is still attached? And how do I determine which of these two points gets the negative/positive?

[@linkshaw7777]

OK, thx for watching... That's funny!

[@bjlrr]

Where would the solder points for the backup power source be on an NES cartridge? Thanks.

[@abstractcottonfield7168]

I would like to do this, but I do not have any soldering tools. Any recommendations for tools for SNES carts?

[@emmettturner9452]

My issue is that the solder points you used may be part of the path powering the SRAM chip and applying heat will increase resistance and possibly cause a chip on the verge of losing data... to go ahead and lose it. :( I'd rather dump the save using an external device (Mega Memory Card or GB Xchanger for GB/C, V64 for N64, Memory Card XP for GBA, Super Wild Card DX2 for SNES, etc). Barring that, I'd rather power it through a cart slot device. The Naki Game Saver+ might be able to do it for SNES games I know that it makes a RAM dump save state and keeps it powered when removed from the console with the cart plugged in to the back but I don't know if it keeps the SNES powered. If you do want to solder to the PCB directly, I suggest booting it again just before soldering to make sure the SRAM chip gets a boost from the console first. Make sure you orient it correctly without the shell on! I recall the Action Replay/GameShark for N64 could copy some game pak saves to the controller pak.

[@SianaGearz]

See, i calculated it, and you shouldn't necessarily worry about that. Resistivity of copper just about doubles when reaching soldering temperature. So if the original resistance was about 0.1 Ohm, (fairly typical of an inch long copper trace, albeit a thin and light one - game carts use much heavier duty, as they must stand up to extended wear), it will be still less than 0.2 Ohm during soldering. Furthermore, that is under assumption that you will heat up the complete copper trace, while that is not the case - copper is a good thermal conductor, while tin is a much weaker one, so the temperature will rise much more rapidly in solder than in surrounding copper area, allowing you to solder before completely heating up the copper - only the tiniest patch of copper will reach full temperature, and only for a very short time. In fact i find it difficult to heat up traces to over 60-120°C over a significant area when soldering. Now we have these batteries which have lasted for upwards of 20 years. Given the capacity of approx. 200mAh, that's 10mAh per year, thus they are drained at a rate of less than 0.01 mA. That times 0.1 Ohm of additional resistance gives you the theoretical upper limit of additional voltage drop off of 0.001 mV at the trace due to its thermally induced resistance increase. You really shouldn't worry about that edging the SRAM! In fact noise generated in the SRAM IC itself is likely to be an order of magnitude higher than that! What you should worry about is shorting something out, as that can make short work of any voltage and retained charge in the IC real quick, so doing an external readout is still a splendid idea. That issue is quite likely indeed, once you start poking your metal bits, like multimeter probes, soldering iron, into the board.

[@emmettturner9452]

Siana Gearz Good info, but the conductivity of the copper isn't the only conductivity that matters: the solder itself gets very hot. The connection between components and traces is not very good without solder (essentially no connection much of the time), which is why we don't just bent the legs. That means electricity flows through the solder and the solder's own resistance becomes important.

[@SianaGearz]

Emmett Turner You still shouldn't worry about that. Indeed tin and lead have thermal resistivity coefficients about 5-10 times as high as copper; however there is a wide but short path of solder, meaning the total resistance of solder in path is still much lower than that of copper traces, even when accounted for changes due to temperature. Indeed good thing those spots were likely actually testpoints rather than something important, because you can indeed temporarily desolder something, which would be bad :P Though not terribly likely. If those are VIAs instead, those must be among the best made ones i've ever seen.

[@drewirons2646]

I was just reading up on this conversation -- so should i just throw caution to the wind and solder a battery pack onto the test points and replace the battery?

[@RETROCUTION]

You're worried about nothing.

[@HomeAwesomation]

I just did a battery swap on link to the past and to my surprise after words my gave save was still there. I was not using this method, I just did a regular battery swap. Any idea how this is possible? I found one forum post where someone else is claiming the same thing for the same game but it goes to a dead end.

[@DUCKxFART]

question about gb cartridge i recently found a ton of gb pokemon games just throne out in the rain they were all moldy i got them all cleaned and working except one pokemon red the nicest looking one out of the whole lot with no outside damage is it possible to clean the circuit board inside some how to save the cartridge from the water damage

[@supersmashdylan]

Not sure if mentioned but I would recommend not using unnamed branded batteries, there is no guarantee of build quality, high mAH etc.

[@IvyANguyen]

IIRC you can replace the Sega Saturn's internal battery fine w/ the console on, & not lose the saves. Do you have any experience with products like the Super Wild Card?

[@holymegadave]

For gameboy carts i use the n64 for backing up my saves. Using the pokemon transfer pack + an everdrive.

[@vacationboyvideos]

I got a question.....my Zelda 1 and 2 for original nes had a battery backup. They stayed "on" to keep the game saved (unlike Metroid that gave u this long codes) but now games I hear don't have batterys anymore. Just like a memory card for my camera...it saves info and does not need a Battery or electricty to keep the info saved. 1. Why did not Nintendo do this? 2. How does a Nintendo game cartridge save games now? ( Gameboy)

[@pierrezapata90]

There is software where you can plug in to your computer with a cartridge adapter and save the files to the computer, then simply perform your regular battery change, and then put the file back in.

[@damian9303]

Is there a device that lets you backup your saves to use in an emulator, or perhaps even allows you to flash it back onto the cartridge if you do end up replacing it after it dies? It shouldn't be so damn tedious to preserve old saves.

[@swagar]

The Retron 5 does this, but flashing onto the cartridge doesn't exactly work consistently

[@VileoSufora4]

The GBxCart will backup your saves, dump your own ROMs, and even write saves back to the cartridge. With that you don't have to worry about the battery method. It can write ROMs too, but most carts are read only.

[@owenjohnston-berresford1970]

I have a game boy colour, on the back of the game case there is a small place for a battery. Is that the battery that keeps the save file running?

[@Wisconsin.pikachu]

Just received a pokemon yellow game in the mail but dont have my gameboy yet I have tested the battery and it is reading 3.25v so I'm happy it is still all original and working ( now I'm wondering if I should just replace the battery and not worry about the save data on it or do I try and save it and see how the kid that owned it before played)

[@bgaming181]

What temperature was your iron to get the battery to fall out that easily and have such big holes in the board? I tried with a similar tip at 370° C and then at 420°C. Solder kept filling up and it was very difficult to get a whole in the board.

[@CkYAll1anc3]

So much better than using a cartridge dumper

[@ZiggyTheHamster]

You should replace your iron's tip with a hook tip or a fine chisel tip. It's a lot easier to work with.

[@ThisDoesNotCompute]

I like the pencil tip on my cordless Hakko iron as it works well for fine soldering, but I have a chisel tip on my wired soldering station. For big jobs, you're right, it's much faster and easier.

[@amirpourghoureiyan1637]

I’m pretty sure a retron 5 can back up your saves, just redownload them to the cart after finishing the mod

[@JSR_]

GENIUS! Sir, this is genius!