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I've been in the Riverwood - Whiterun area for hours, for 50 saves. And yet still I can not get out of the loop. My game is modded with the likes of Open Cities, HD textures, Texture Combiner, SkyRe, SkyTest etc. Everything works fine. Except if I have my .ini's on standard, the game always freezes whenever I get to Whiterun, be it near the Giant and the Companions, or a little closer in town. It doesn't do it in Helgen, in Riverwood nor the dungeon in the mountains of Riverwood.

Then I tried some tweaks and then I suddenly get no stuttering and no freezing, but instead, it randomly CTD's. I'm even scared to press journal with those tweaks, it will ocasionally just CTD out. Funny thing is I blamed Dawnguard for it, but it's not Dawnguard. Because sometime ago I reinstalled everything without Dawnguard and it did it too. I practically need to make it a full time study to every wonder what is causing it. It find it hard to imagine it is one of the mods, because I tried to turn some on and off and it still did it. Plus, the tweaking affects the problem, the freezing turns into CTD's and no stuttering when in big area's.

Spending hours just to get inside Whiterun and move it on has left me with the Hotel California syndrome. Trying the uGridsToLoad and uExterior Cell Buffer set on 7 and 64 didn't do anything either.

It seems after posting this it went a bit better after I rebooted the .ini files completely. Now the CTD's are less frequent. I am actually past Whiterun now.

Have you tried stepping away from the ini and just running at a lower resolution for a bit, and switching back once you're out of the area?

Worked for me.

This copypaste line worries me a bit: "In SkyrimPrefs.ini Add/Edit:" as it suggests you have some tweaks in the wrong ini.

I removed those mentioned tweaks, because in the end, it seems like it doesn't do anything. Funny thing is it never crashes in interiors, only outside. I'll try a lower resolution perhaps, although that's not ideal because to fit my monitor only 1920 x 1080 actually works.