What? Please give examples of what ntrboot can do more than a hardmod. With a hardmod, it is impossible to get a permanent brick other than hardware issues. I have a hardmodded o3ds and n3ds, and I did both myself. I do not solder professionally (evident in my bricking an OLED Switch on my first attempt... went too cheap on the microscope...)
I was exaggerating a bit with "soldering professional", since we have had a few threads where the hardmod attempt resulted in physically broken motherboards. I'm not good at soldering myself, but successfully hardmodded a DSi which is of comparable difficulty, despite my movement disorders/tremor.
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What can ntrboot do more?
Repair software, including software based 8046 BOOTROM ERROR, even without an existing backup. That is a huge advantage for ntrboot – not with hardmod, since we do not have the decryption key. When obtaining a bricked 3DS, you'll rarely have a backup or the OTP. Have you never seen statements like
"I have no NAND backup." ?
Since the hardmod B9S installation relies on a
known plaintext attack, we must obviously
know the plaintext (firm version) or try them all. Tedious.
If the FIRM partitions have been trashed
"accidentally", like some people call damage they caused messing around, the hardmod will not allow B9S installation since there is no way to know what to write.
With ntrboot we have access to the OTP and readily available software installing CFW (SafeB9SInstaller) regardless of the content in
FIRM0/
FIRM1
I've no idea what to write with hardmod in
this case if no backup exists (might still be possible, I don't know if this sector is also encrypted). GodMode9 contains a rebuild NCSD function, I didn't try it yet.
Does more? No way. Direct nand access.
The direct NAND access is inferior, since we cannot use the crypto-engine for encryption/decryption and writing arbirtray stuff on file level. Normally the hardmod is/was used for installing CFW and is rarely needed again. Full direct (unfiltered RAW) access is given in software as well, so not a hardmod-only thing. All in all I can't see anything that hardmod can do, but ntrboot not – only the other way round… and that combined with the arguably higher risk when soldering.
Hardmod was interesting before ntrboot was available. I wouldn't recommend doing this now (except maybe for learning/testing).