Yeahhh I have an i3 with 4gb of ram, but Intel 4000 integrated graphics. Is there even an ENB that I could run without it slowing my computer to a crawl? I can get around 45 to 50 fps without NMC's texture pack and 100+ mods (so pretty much vanilla). Thanks in advance.

Maybe just use nevada skies and wait until you have a more powerful computer to try ENBs, because their is mods that improve the graphics at a lot less of a performance cost, but if you really want to use one try Old World ENB without depth of field and advanced shadows.

Just use nevda skies and Ojo buneo texture pack it'll look great and you won't get much of a performance loss dynamo enb doesn't have to much of a drop i'd say try some out and if they don't work you could always just delete the enb stuff from your fallout nv folder

You can learn how to customize your ENB.ini or use Blackout ENB or more modern D3d9s which allows you to customize the features in-game by pressing Shift+Enter, once you disable some heavy post processing you can enjoy the Occlusion/Depth of Field/etc.
ENB makes your rig slow because it uses too much post processing so by reducing its usage you may drop only a few frames per second.

I believe you can get more performance by disabling AA and Ambient Occlusion in the enbseries.ini. But your games will have some weird edges and some incorrect lightnight.

I know that with the 780 gtx ti, if u run blackout enb vanilla u might have a chance to stick to 30 fps. I would suggest dynamo. But i have been having problems getting that or any enb to work. I say what other people say, use something like NMC/OJO bueno/ Poco beuno, and project reality, nevada skies or realistic wasteland lighting pluss dynavision 3.

If you're using integrated graphics, I would recommend giving Realistic Wasteland Lighting a try. It has its issues, but offers a lot of improvement over the game's vanilla settings, with practically no performance lost. Use to use myself before upgrading my PC.

i dont know how to speak tecky talk but i think your rig needs to be a bit better and anything with nivdia would be a good choice but maby you could run an enb i dont know for sure though