Hacking Best way to write back-up NAND to O3DS?

[FF777]

I bought japanese O3DSLL super robot taisen version from chinese "play-asia" site.. It was expensive..
Had firmware 4.5.0J..
Bought gateway card..
Backed-up NAND to computer (using gateway card) >NDS.img
When I play games, 3D mode looks blurry, but 2D mode works fine..
Try to RMA it for a replacement by sending it back to play-asia..
They tell me they checked it twice and nothing wrong with it..
I think they are lying so they don't have to send me a replacement..
They send me back the same O3DS..
I figured I can give it to my sister or some one and tell them to only play in 2D mode..
Turned it on to check that it still works..
Found out those chinese people updated it to newest firmware 9.4.0!!!!!!! (newest at that time)
Never ordering any thing from them ever again..

I have never soldered any thing in my life before, and I would have to search and buy tools to do it..
So here are some questions I have:

1: Is soldering and wires the only way I can restore NAND?..

2: Are there any recently found ways to downgrade to a previous NAND on O3DS?.. For example, KARL3DS, or even using a sky3DS card to boot gateway and some how do some thing magickal?..

3a: Why is my NAND file a different (smaller) size than the NAND size in this video?:
I used gateway to back-up.. He uses hardware wires to back-up..

3b: Does backing-up with gateway card, and backing-up using hardware wires (like in that video) always give different file sizes? And if so, why..

I don't want to brick 3DS by writing a NAND image that is smaller than the 3DS is expecting..

 

[NicEXE]

head over here: NAND

 

[FF777]

head over here: NAND

Ohh, thank you.. I had seen that page before, but forgot it had hardware hacking instructions on it..
With that page, I now realize the reason for the size variation on my NAND back-up and the back-up size in that video.. The guy in the video's 3DS must be using a samsung chip, and my 3DS is using a toshiba chip.. My size seems correct now after looking at that page..

I suppose I will wait a little bit and see if any one else posts any other options.. If not, I guess I will start looking for all the tools needed to do that hard-ware modification I guess..

 

[thorasgar]

Hundshamer and Avalynn do mods in the US. Contact them.

The other option is they are all the same on the inside and you can switch motherboards.

 

[MelonGx]

SysNAND >= 9.3 --- Hardware mod only