====== REAL SOLUTION FOR STABLE UGRIDS ========
==============================================
[I've added my experimental fix into my files too, of course with a credits for this tweak from AltimorFP and Safety Load mod too, they greatly helped in experimenting but i had crashes and freezes with them alone too, until i made that crazy fix from below]
http://skyrim.nexusmods.com/mods/48387

Well, im playing with ugrids from Oblivion times, and a lot from Skyrim 11.11.2011 premiere.
I have nice rig, quad intel, 8gb ram, asus geforce 780 direct2cu oc . Im also big fan of Elder Scrolls (playing since Arena) and modding too.
For Skyrim , right now i have around 240 mods installed and active (hell lot of hd tex, ENB , weather etc. too) , i know how to use Wrye Bash, TesEdit, call me experienced user.

Now finally i have stable ugrids but AFTER i made small tweak to well knwon settings, and using this dll file helped me a lot becouse
i was free to experiment without taking care of saves.
Im using ugrids 7 becouse rest of higher ugrids makes bad things happens at various mods (quests/scripts) and vanilla quests , trust me im playing with these settings for 2 years and having a few weaks of gaming fuc..d up is not worth using 9 instead of 7 .
But there WAS ONE THING I NEVER TRIED for Skyrim uGrids, i always followed that stupid formula for exterior cell buffer : 36 / 64 /100 / 144 etc.
Well , even with this litttle mod i still get crashes while zone transitions (when engine was forced to load new cells - its a simple limitation of engine).
I was really angry and i changed exterior cell buffer WITHOUT mathematic pattern as it is given on all sites to the value = http://forums.bethsoft.com/topic/1482399-uexterior-cell-buffer1024/1024.
And guess what?
Im playing Skyrim with ugridstoload at 7 and exterior cell buffer at 1024 for last 7 hours without single crash!
I know its completely unlogic but HEY, SCREW THE MATHEMATICS! Its working, and yes keeping high range detail views!
It looks like engine was choking and don't have enough "air" at exterior cell buffer set to 64 while ugrids was 7. It was easy to observe while in same places where at "64" game freezes and ctd to desktop, new "1024" exterior cell buffer modified value let me play trough critical moment (and i can tell exactly where this moment was becouse of few miliseconds "choke" of graphics , hard to see but after this less than second moment game let me progress).
So experiment, start from 1024 exterior cell buffer and go further up to 4096 or more. I sense pattern here. And it is working.




So enter your Skyrim.ini look under [General] section and copy/paste below 3 lines:

uGridsToLoad=7
uExterior Cell Buffer=1024
bPreemptivelyUnloadCells=1

Then save, and check ingame .
OF course use this mod by AltimorFP becouse it let you revert to previous safe uGrids settings (ugrids=5 /cell buffer = 36) without losing save or character or using console [place .dll file into SKSE plugins directory].


Im using SafetyLoad also (little mod here on Skyrim Nexus, (download extract and put into SKSE / plugins folder in Skyrim data directory) .

"BUFFER" means place for temporary storing something, well it looks logical to me when we use hell a lot of textures, supported by ENB profiles and other graphical and heavy scripted mods (like quest mods, mechanic mods) , each cell of the world (and in this engine whole world of Skyrim is divided into cells) takes more place than programmers planned.

We have similar (but hidden) INTERIOR BUFFER for interior cells, while buffer from above is for EXTERIOR cells (everything outside dungeons, homes, catles, inns) for open world.

And i just imagined that we let that old engine handle 7 grids full of cells to work at once , with all that mods and oly 64 of "somethnig" buffer. And what if that means some kind of memory space? While not let it use more and see what happen? Maybe it works similar to memory (those 36/64/144/looks familiar. 4x64 is 256, so maybe i should give 256 for exterior cells (4 x more "space") , and what if we make 256 x 4 , well we get 1024, looks bit familiar eh?
Maybe it's just a symbolic engine coded memory reserve for exterior cells which filled those "grids" ?
SO let's give that 4096 even (if we have 8gb of ram).
You will gain a lot of FPS too.

Now i don't have any freezes and CTD, only delicate, lasting 1-5 miliseconds freezes while i have cell transition, and not every time.

It looks like we have been searching cure for that problem for 2 years from completly wrong side. It is not matter of our hardware or Skyrim engine limitations , but matter of harmony between our hardware and that engine.
It's not kind of magic its pure logic.

All these guides about ugrids were pure myth leading nowhere, i always wonder why i can't use more ugrids in this game while i can see and use whole gigantic map full of scripts in arma 3 for example wihout any crash and great visual range (many kilometers). All info we get from all uGrids guides on different forums was that "we must use exterior buffer 36/64/100/ etc. " , but why so little i asked today? And i was right, i feel so stupid that this simple question takes me 2 years to ask .

HAPPY GAMING!

In similar way i've made simple fix for Requiem and Deadly Mutilation which let both mods works togehter (check my files section). Sometimes bit of curiosity can give us great results

I hope i made nice present for other UGriders , call me Santa Claus! Ho ho ho.
I don't care about credits, im happy if someone make use of that observations and tweak, and if that tweak give as much joy as it gives me for last 9 hours without single crash .