[Galaxy Note 4 Android Development (Snapdragon)] logosA:
I will try here to make a sum with everything I have learned in these almost 12 months that I am dealing with that problem in my phone, as most of us have.

First of all, you have all to realize that this is a hardware problem.

Its NOT a software update or some app that went wrong , or even a bad battery.

All these are the result of a hardware defect of the motherboard, which step by step is leading to one or another degree to the same result : emmc failure.

So dont look to find a cure in these, its just the beginning and will spread if you continue to think nothing is happening and what happens to others, is not your problem.

In the other hand, not every freezing and lagging and restarting means its an emmc failure. it can be software which usually when find what is causing it , goes away and never comes again.

But when is that what we are dealing its not going to go away.

The only way is to replace your motherboard with a new, original, motherboard, preferably bought and replaced by a Samsung official support center.

I know it sound a little advertising, but the reason I am righting this, is because are getting more and more people that bought and replaced their boards with second hand or unknown origin, boards and after not long time they are having again the same problems.

Its very expensive to do that, so if you dont have guarantee left to cover you up and you want to stick with that phone as long as you cant, until get tired or not able to do anything else, follow the road with the software solutions that you can find here, which for me is the best thread supporting the condition of our phone

(I think I have read everyone available in the net, for the past 11 months and I am still following all of them).

1.

Sdcard with the unbrick image on it

.

You dont have to use it if your phone is getting to download mode by its self.

this method is for people that their phone are completely dead and do not respond in any actions of the user, just an expensive paper weight , in these cases (mine is that) we have no other way but to use the sdcard to make our phone boot and get to download mode, so we will be able to flash the repair stock rom and try to get it back to life.

Usually phone that heavily bricked have to be freeze along with the use of the sd card to be resurrected.

2.

flashing stock rom or a repair stock rom.

The difference between these is that stock rom is one file which is flashed all along, though repair stock rom is a stock rom divided in its 4 original parts (BL= bootloader, AP=ROM, CP= modem, CSC= COUNTRY, region, model)

When a 4 set repaired rom is flashed through odin, every part is flash after the previous has been flashed successfully and that partition has been closed before proceed to the next. This is the reason most of the times the unbrick is done with the use of the repair stock rom and not the single file- stock rom.

When we try to unbrick one phone, first thing we are trying is flashing the stock rom, that our phone had the moment the problems shown up. If that fails, then we move to the repair 4file set rom, if that fails too, then we try the use of the PIT, along with the repair rom, as partitions on the phone may have been corrupted and phone is not able to define what is what. So its not necessary every time to use the pit file when we flash a stock rom. PIT is included in the rom its self.

If one time has been done and flashing was successful (odin says PASS), even if the phone after that is not able to boot again, we dont need to use pit again, but just re-flashing the repair files is enough. Sometimes it has to be done again and again the same process until the phone is totally unbricked.

First conclusion, maybe one time is not enough, dont give up , try again and again.

3.

freezer, why does it help?

Freezer keeps the CPU cool because overheating make the motherboard's contacts around the emmc to fail

Samsung have put ram and memory together in a single chip and fixed it on a CPU so that CPU can access them much faster, but the heat of CPU melt the connections of emmc and so pass of the data becomes impossible.

When the phone is trying to flash the rom , CPU is working in top rates , overheats the board and the connections with the emmc become loose and emmc FAILURE appears.

Some people are suggesting also to hard press the phone on where the sim card is while phone is booting, as the CPU is placed right under that, so we help it a little more to have better contact and boot up.

Second conclusion, freeze your phone before trying unbrick and try to keep it as cold as possible, during the whole process.

4.

What rom to choose to help me unbrick my phone?

These days we have a lot of sources to get in our hands the original stock roms from Samsung to help us unbrick our phones:

http://updato.com/firmware-archive-select-model?q=SM-N910F&rpp=15&order=date&dir=desc&exact=1

this is the easiest and faster way to get in hand your(one file) stock rom, without waiting ages and registrations and hidden things, just use your phones mode code and you will find the latest available for your phone/region

Repair stock rom is not hard to find, as well, all you have to do is :

download this (windows ) application and install it on your windows pc. This is the application that will allow you to search and download the latest stock rom for your phone. (dont pay attention to outdated that is saying on the page , its a marketing trick to lead you somewhere else)

choose samfirm 3.06

extract it on a folder on your PC and run samfirm.exe

in the opening menu type

SM-N910 XX(your phones model code ex F, P, WO, etc)

REGION..... xxx (your region country)

tick '' BINARY NATURE''

CHECK UPDATES>DOWNLOAD

THIS WAY YOU WILL GET THE LATEST STOCK REPAIR ROM FOR YOUR PHONE/REGION

Binary nature means the rom split in 4 files(REPAIR ROM)

This application can also give you the stock rom, if you untick BINARY NATURE.

If the stock rom (one file or 4file set), is not helping you, try some other one, maybe a older one can do the job better .

IF FINALLY FIND IT, KEEP IT SAFE, you may be need it in the future as well.

When your phone is unbricked, dont think everything is over.

Making the same things you did in the past may make it break again. So no heavy gaming, no fancy modes, no stuff that may put your phone in risk again. Keep in mind:

ONLY MOTHERBOARD REPLACE, can make your phone as it was before.

These are some of the things I have learned.

I AM SORRY FOR THE SOoooo long post

I hope someone get some help of that

Good luck to us all