... As I said... it's not enough to just plop on a new chip from somewhere else and do the standard iOS factory image restore process without extracting info from the original and putting it in the new before soldering. This information prior to the milling is omitted from the video.
There's a tool for that (many, many of them), both software-based and physical-based tools that can copy out the SysCFG block and write it into a new chunk of flash.
I’ve seen several videos by reputable fixers that demonstrate empty NANDs working fine with DFU factory restore.
Same situation on Mn MacBooks.
Would be weird in the actual mass production process if the flash would need to be pre-programmed somehow; one DFU process IMO must be able to do everything needed.
After watching a couple of videos, that works with some older versions of DFU software and not new ones. Might be an arbitrary restriction by the DFU update software rather than the hardware. I'm sure they know this and work around it of course when doing these FLASH swaps.
Also if there are two flash chips they need to be installed in a certain order. Not sure of the rationale behind that precisely. I doubt it's a hardware difference.
