Duplicate copy of data on system memory and USB questions


Well-Known Member
Apr 11, 2015
United States
I got a few questions about scenarios having duplicate copies of a game or app on both system memory (will call it sysmem) and the USB drive or physical disk and USB behavior in general. Trying to be thorough in case anyone else wonders.

First, I know according to Nintendo that if you copy data from sysmem to USB or USB to sysmem, it always stores (and obviously loads) any new save data to USB, and sysmem is ignored. So...

0. I assume this means even if you copy only your game data to USB, leaving the save data under only the sysmem copy (either by having no save data before copying and playing with the USB unplugged and plugging back in, or deleting just the save data under the USB copy), it will still save any new save data under the game copy on USB, [this>] even if the USB duplicate had no save data under it? (but what happens to your sysmem save data?).

1a. Related to "0", I might test these with a small game... but if you copy a game with no save data from sysmem to USB, unplug the USB drive and play it, then plug the drive back in, will it act like there's no save data as long as the drive is plugged in, or again, will it still load the save from sysmem with the USB plugged in while the USB duplicate has no save?

1b. Alternately, if it does still load the sysmem save, will it again save the new save under the USB duplicate with no save data?

2. Does anyone know if the Wii U actually loads the game or app data itself, not save data, from sysmem or USB when you make a duplicate copy of a game or app to USB? Or if which copy loaded depends on which is the oldest or newest (not save data)?

Use would be, if you just copy a game from USB to sysmem to play it, it could load the game data from sysmem and only save to USB, saving reads from the USB and only reading and writing save data to the usb duplicate. Then when done playing, delete the game from sysmem since the save is still on the USB, rather than moving everything to sysmem to play, then moving everything back to USB when done.

3. If you copy a game to USB, then unplug the USB, install DLC and/or update the game (make update data) on the sysmem copy only, and plug back in the USB, will the game load with the update and/or DLC, or act like it's not installed since it isn't installed on the USB copy, or will it actually prioritize whichever copy has extra stuff installed?

I assume with the above, the Wii U will just ignore any game/save/update/dlc data on sysmem if a copy of the game data alone is on the USB.

Now, what about disk games with no game data installed...

4a. If you have a disk game with save data on sysmem only, will it make all new saves to USB when it's attached or still save and load the sysmem's save data? It'd be stupid if it doesn't just load from and save to the same save data on sysmem, I wouldn't want to have to keep moving the save back every time I unplug the USB.

4b. Also, if you have a save file from the disk on sysmem and create a copy to USB, will it now save and load from USB only?

I'm planning on making save data backups to USB drive that I'll only plug in when I want to get data from it.

5a. Now for the more complex questions... say you got the digital version of a game, got any update or DLC, and have that, and possibly a save file, anywhere (sysmem or USB), then put in the physical disk copy. First, will it load the physical copy or the digital copy?

If it loads the physical disk instead of the digital version, will it load the physical version with the update, DLC, and save file that's under the USB digital copy and save to the same file, essentially making it interchangeable if you play with or without the disk? Or... will the WiiU act like there's no update, DLC, or save data until you delete the digital copy's game data or something?

5b. Alternatively, if you delete the digital game copy but not it's update, DLC, or save, will the physical disk still act like none of that exists?

I don't know if the physical version will make it's own data or use the digital copy's data.

This is a duplicate problem in which it would make you have to have duplicate copies of the update, DLC, and save data to play the physical version.... I got DLC for a few games for the physical disks I don't yet have on Wii U, and a few of those were the $3 sale Capcom digital versions, so they have their updates and DLC, and it would be a big problem if later, after the inevitable full closure of the eshop, one gets the physical version and wants to use that instead but can't use the update / DLC data saved under the digital version duplicate, and can't redownload it anymore.

6. Related to "5", if the physical copy doesn't share (esp) update / dlc / save data stored under the digital game copy, and you put in the physical disk, and it says there's an update that starts downloading, will it overwrite the update data under the digital copy and mess that up, or create a different data spot for the physical version wherever the digital version isn't installed?

I assume it must prioritize which version loads to avoid the above scenarios, but how, I don't know... especially if #7 below occurs. The digital version has its own icon in the menu separate from the inserted game slot, so I don't know if it will ignore the physical disk inserted if it already has the digital version in the menu, or if, even if you click the icon of the physical version, it loads the digital one anyway until the digital version is deleted.

7. If it prioritizes the physical version over the digital, I don't know if it will accidentally overwrite the save data under the digital version you have on a USB by mistake if you played the physical version with the USB unplugged with its own save on sysmem, having a different save file between the physical and digital versions, then put in the physical copy with the USB plugged in. Would it then load the physical copy with the data it was using on sysmem, or load everything from USB again, or will it load from sysmem since there's a digital copy of the game with the USB data?

There's other duplicate data scenarios I wonder about like if you have a duplicate of non-save data and load the physical disk, if it will load that data from sysmem or USB first. Also other scenarios where you have different data under a copy kept on USB than on sysmem playing the disk with the USB unplugged.

Unfortunately, I can't test having both physical and digital at the same time since I have one or the other.

Two more questions closely related to the above, but for the 3DS... If you got the digital version of a game so you could grab the DLC (and any required update to launch it), then put in the physical version later on, would the physical game start up with the DLC?

I noticed when I went and installed an update from the eshop for a game I had physical before putting in the physical game that it didn't have to update. The updates I manually installed seem to apply to both versions as it also installed on digital version games that have physical versions. I hope it shares DLC data.

And second, if you play awhile in the digital version, will the physical version load that save file? I'm assuming it doesn't share saves only because that data is saved on the cart in physical versions. But I still hope it shares any other data, otherwise how would it act if you had both, since all data for any game only has 1 entry, including updates. I can't test this either right now.

Anyway, if anyone answers, I'll put the answers in bold under my questions whenever I see them, and add any other questions that might pop up about any duplicate data scenario, either with having a duplicate of the digital game on sysmem and USB, or both the physical and digital versions with duplicate data on both sysmem and USB. Some of these are probably answered around, but I wanted to get it all in one post with quick answers under each question.

Site & Scene News

Popular threads in this forum

General chit-chat
Help Users
    Psionic Roshambo @ Psionic Roshambo: Ancient Toaster Oven From Florida