Some key posts on this and related threads (experts feel free to note any errors or insights): Post #11Post #27Post #40 (this is where the 500/430 ratio seems to have originated.)Post #66Post#278Post #313Post #1 (adjacent thread: Caution about memory optimisers)Post #64 (adjacent thread: Caution about memory optimisers)Post #68 (adjacent thread: Caution about memory optimisers)Post #70 (adjacent thread: Caution about memory optimisers)Wiki article (draft) Thanks, STEP OP follows First of all I wanted to thank you all for the great work you have done with STEP. Skyrim is the first game I installed on this computer and you guys have made it an AMAZING game. That being said, I have an issue that I hope you can help me solve. My setup: Vanilla Skyrim gtx670 w/ 4GB @1080p w/ latest driver 16GB Memory 3770K at about 4GHz Windows 8 64bit ENB 149 Ultra settings Highest available texture/quality Mod Organizer Step 2.2.1 + Skyrim Revisited + others I have noticed a post here and there saying that Skyrim can't really address more than about 3.1GB of memory without issues. This seems to jive with my experience, meaning I CTD every time my memory hits that mark, but I couldn't really find anything definitive on the topic. The issue with googling the topic is the pre 1.3 skyrim that couldn't address more than 2gb of memory. My mod list is mostly based on STEP which is why I came here for help, with about ten mods added onto the end (Interesting NPCs, Detailed Cities, Economics, COT, and a couple others). The reason I haven't included my mod list is that it doesn't seem to matter. As long as I keep the memory usage below 3GB I can have pretty much any combination of mods. What I have tried so far (in no particular order): resetting ini filesremoving enbnot using attkltonly using a new gameremoving all mods and adding one by one until issue crops uprunning as adminwatching the papyrus log - it seems relatively clean, no obvious errors right before CTDYes, I can run STEP just fine without any issues, but I also never get near 3GB of memory. I have tracked VRAM usage as well and have seen a max of 2.7GB/4GB. As an example of where I might run into issues: I start a new character with Alternate Start. I start with Breezehome. Run out of Whiterun, past the Brewry, up the hill to the bandits. Enter the cave (watching memory usage with Elys MemInfo), and it dies right after I see 3GB. I have this same issue not using AS, sitting through the intro, and then running over to whiterun. I'm sorry if this post is all over the place. I have spent more than a week trying to solve this issue, and the only solution I have found is to reduce memory usage. I have got to the point where I can exchange two texture packs and get into the cave without a CTD, but with both I get a CTD. I didn't even think texture packs should even affect CTDs, but I'm relatively new to Skyrim on the PC, so I could be wrong. I also found I could get a bit further with ENB turned off, but would still crash once I got above 3GB of memory. Finally, if I reload a game after a CTD, I can play just fine...until I reach 3GB of memory. I really hope you guys can help. I more than willing to try anything at this point, besides just disabling all of the mods.