General Performance
uGridsToLoad=5 - This variable does not exist and need to be added to bottom of the [General] section of the Skyrim.ini file to be implemented. It controls the radius around the character within which the engine loads up the most detailed objects, characters and terrain. It can have a substantial impact on both image quality and performance. Any value assigned to this variable needs to be in odd increments, e.g. 3, 5, 7, 9, 11. The screenshot comparisons above demonstrate the way in which there is progressively higher detail in the distance as the value of this variable is raise.
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While altering this variable is tempting given the image quality improvement it provides, you should experiment with any uGridsToLoad value in various areas, particularly those where you usually experience the lowest FPS. The default of 5 is already a good compromise of performance and image quality, but if struggling for FPS, you can drop it to a lower value such as 3, though Bethesda strongly advises against this as it may lead to game instability.
Importantly:
Aside from lowering performance and causing potential instability due to the greatly increased resource usage when raising uGridsToLoad, if you save a game after you have altered this value, the new value will be incorporated into your saved game. This is worth noting because the game only allows you to load a saved game which has an equal or lower uGridsToLoad value than your current value; you will not be able to open a saved game with a higher uGridsToLoad value. This means if you lower your uGridsToLoad value again, you won't be able to load up the saves which used the higher value. So you should extensively test any change to your uGridsToLoad before committing to saving the game. If you need to revert a change in uGridsToload in an existing save game follow the steps below:
- Start Skyrim and load up a saved game.
- Use ALT+TAB to switch out of Skyrim and back to your Desktop.
- Edit the Skyrim.ini file as normal, modifying the uGridsToLoad variable to the desired lower value. Save Skyrim.ini and close it.
- Use ALT+TAB to switch back to Skyrim.
- Open the Command Console using the tilde ~ key and type refreshini.
- Save your game to a new save slot, and it should now have the correct new uGridsToLoad value.
uExterior Cell Buffer=36- This variable controls the number of world cells (controlled by the uGridsToLoad setting) that are buffered to RAM to provide smoother transitions and improve stability. The general rule for the optimal value to assign to this variable is to take your current uGridsToLoad value, add one to it, then multiply it by itself. For example, if you set a uGridsToLoad value of 7, change uExterior Cell Buffer to 64.