you could try this http://www.nexusmods.com/skyrim/mods/50305/? , it's just a dll and ini file (which has descriptions in it) that changes the start up/first memory usage allocation from 256mb to 512mb, you can alter the ini to make it higher if you want but i'd stick with the initial settings for a fair while just to make sure. I had similar problems with similar rig (more ram but the hard cap in latest bathesda update is something like 3.2 gb so that doesn't really matter) then it ran way better, after that i set everything to medium and knocked the fade distance down a notch or two and it runs like warm butter (at least untill the next BIG mod or i can afford a WAY better graphics card. these are just my personal experiences and in no way gospel but it could be worth a go. hope this helps *and as the post above states, do please watch that video and subscribe to gophers channel, not just for mod review (although they are really good), but some of the installations instructional videos have saved my butt in big ways, in short gopher rocks !