With that mod stability on Oblivion is actually improved and is, unfortunately, not available for FO3/NV in a true form. *Exceptions are the handful of Oblivion mods like Streamline that actually fixed issues in the underlying issue. To the point that all DLC for every game since Morrowind has been nothing more than an official mod**. Aside from content conflicts (which rarely cause crashes just make things unavailable or visual glitches) or script mods eating up CPU (Oblivion's 'Cats and Rats' mod was notorious for this) there's no real impact to stability WRT installing mods*. For example: FO3 was crash-happy for me on Vista but NV was rock solid under 7 (on the same hardware) until I installed the Honest Hearts mod.īoth were 'heavily' (scare quotes used because even the most heavily modded installation of Fallout comes nowhere near an actual mod heavy Bethesda game, I think I ran about 60 total between quests, tweaks and replacers whereas with Oblivion I had to use Bash to merge quite a few to keep under the 255 mod limit and my playthrough of Morrowind a couple of years ago featured around 150 distinct additions) modded installations.

They fixed some of the memory management issues that Oblivion had but the crashy and shit memory subsystem that Oblivion used is still in play for the Fallout games and it can rear its head or not based on the system. That's, unfortunately, normal for FO3 and NV.

Fallout 3 gog crash