that is an insanely huge save game. Anything over 50 megs can be difficult to load. Your skyrim game will only use up to 4 gigs of ram regardless of how much you actually have...its a bethesda thing. Secondly, your save game details not only your completed quests but what things are out of place from their default locations. If you go to an area and move everything floating freely in that cell to somewhere else, the game records that in your save game and when you load that cell, it must retrieve that data from your save game. When you go to a new cell, it does not remove the data from the last cell you were in from your ram, it simply adds to it and eventually is too much for your machine. load your current save game and every time you go to a new cell, console command "pcb" for purge cell buffer. If this fixes your problem it means you were running out of memory either from the hi res textures or the save game. Im level 48 and have 100 quests under my belt besides the main, DB, and winterhold stuff, with 20 mods and my save game is only 11 megs. It is because i dont pickup and drop everything i see, nor do i run a zillion aftermarket weapon and armor mods.