I recently upgraded my rig (see sig). And man was it a difference. In Markarth I used to have 25 fps at the worst place. Now it has doubled to 50. At top of Dragonsreach it's 70+. Same in Solitude. And Falkreath is a solid 85+ no matter where I stand.

Anyway, I thought it would try a different ugrid setting. Has anyone experimented with this? What is the best and most stable value which gives the best combination of view distance and performance?

Also, if I change ugrids, are there other settings I must change as well?

Finally, will changing ugrids affect my savegame?

yes make backups of your save game first!! ...and your ini's

when you change the ugrids you have to change the uexterior cell buffer(also in the ini)

ugrids 7 seems about the most stable.

also use that skyrim configurator you can easliy adjust the setting from that.

back up your save games!!!

Raising uGridsToLoad above the default of 5 does have an impact on framerate, but perhaps a larger impact on VRAM usage. I have used a value of 7 for a while now and I haven't experienced a single crash. With only the High Resolution Texture Pack DLC, at 2560x1600 resolution my VRAM usage caps out at about 1450MB. As my video card only has 1.5GB of VRAM, I haven't felt compelled to try a uGrids setting of 9 or above. The primary reason I chose to use 7 is to render waterfalls properly at normal and extended view distances. With a setting of 5 they will be shown as static blocks until you get rather close. They still don't render in the far off distance, but I'm fine with this.

The uGridsToLoad setting gets saved in the save game file and Skyrim will fail to load a saved game that uses a higher uGrids than what is defined in Skyrim.ini. You should back up your saves before making a change to uGrids, but even after saving, you can still revert to the default value by following this procedure:

1. Load your save game
2. Alt-tab to a text editor, edit uGridsToLoad and Exterior Cell Buffer values, save Skyrim.ini
3. Alt-tab back to Skyrim, open console, type 'refreshini,' close console
4. Create a new save, exit Skyrim

Your new save will use the new uGrids values and Skyrim will be able to load the save. Higher values of uGrids will tax your system considerably. For general play, a setting of 7 is probably as high as you want to go due to stability and performance concerns.

yeah 7 is the best way to go, but 9 aint bad either, but if your gonna use texture mods id stick with 7, for me 7 has been perfect, 5 is just god awfull, just know that once youve played with higher ugrids, if it doesnt work out youll go mad cuz youll have seen what it can look like lol.

I've never felt a need to raise it beyond the default of 5. But yeah, VRAM and CPU is what will be stressed the most.

I tried ugridstoload 7 last night and it's a great improvement with no fps hit for me. Except around riften land, because of the flora overhaul plus my hd textures. I get 40fps there with ugridstoload 7.

Is it worth it for that reason do you think? Or should I sacrifice flora overhaul for a steady 60fps everywhere with ugridstoload 7?

I've been thinking about ugrids of 7 for awhile now. I have a similar system as you with really good performance.

Have you measured your vram usage? And importantly, what resolution do you use?

I haven't measured mate no. I'm at 1080p, 2x AA and FXAA.

Around riften I was low on VRAM, was getting low fps and 2-3 second pauses. That's with hd texture mods and flora overhaul to though with ugridstoload 7.

On the tundra it was silky smooth 60fps.

I'm at 1024 for vram and play at 720p. Last time I measured I was in the 900's for vram usage. Darn it. I really want ugrids 7, but I just don't think it will work. Also, followed the nvidia guide about 2-3 months ago, and kept ctd when at 7. That was a couple patches back, and w/o hd textures.

Does anyone know of a website or tool that shows how much vram is used at different resolutions and ugrids?

Not that I know of mate. Easiest thing to do is try it, and have MSI afterburner running to monitor VRAM. Changing ugridstoload only messes up saves if you save with different values.

Change to 7, load a save, watch the gpu etc. then just quit and put it back to 5 if you need to.

There's a chance you may be able to keep both. To my understanding, the reason for the greatest impact around riften is due to the falling leaves in that region of skyrim. There's a mod available that decreases Beth's original 1024res leaves to a lower Res which has a substantial impact on performance. Apologies I can't state the specific name, I'm not on my rig currently, I believe its called better performance leaves, or something along those lines.
The leaves fall in such abundance and quickly that the detail is not really notices or missed when lowered.
I too enjoy the high Res floral overhaul and HD textures, which is why i was surprised this mod didn't disappoint.
There's a good chance that the high qty of those high Res leaves multiplied by the ugrids increase, could be rendering in such abundance that its causing that lag.
the mod author even offers several different versions/Res.
It may be worth at least trying before you decide to completely remove floral overhaul, especially since your only getting the negative impact in the riften region. Hate to have the one location require the removal of floral in the entire map.

Thanks for the tip man, I can only find a mod that removes falling leaves altogether on the nexus. Will keep my eye out

just found what i was talking about
http://skyrim.nexusmods.com/downloads/file.php?id=6387

took me a moment to find it as well. he changed the name since i tried it back in january.
Hope this works as a viable middle ground to your dilemma

Thanks for this mate. Disabled flora overhaul though to check and it had no effect. It's just when I enable ugrid 7 that I go to 40fps. It's the little island you can't get onto near Riften that's the trouble. Plus I get horrible stutter every 30 seconds or so.

I think it's my CPU though. My GPU usage was at 70% max, mostly 50%, and VRAM usage never went higher than 600mb (I have 1280mb).

That leaf mod seemed to keep things even smoother though in the Rift so thanks for sharing I'm back to using all my HD mods and Flora Overhaul