As an (ex-) dinosaurus user, I recently bought a new laptop, able to play Oblivion on max So I wanted to use the mods that always looked so good but I was never able to run on my PC. I installed Better Cities and Let the people drink!. There is only one way to explain what went through my mind the moment I was exploring the IC Market District:

Are there any other big mods like these guys? Now I know why people can't play with mods like these....

Unique Landscapes springs to mind. But if you load up your laptop with a lot of mods, its going to start to lag, particularly outdoors. I've got a pretty decent laptop, but with Better Cities, UL, and everything else I have got, it lags a fair bit in exterior areas, especially if extended combat ensues. Interiors are usually fine. So, now I am building a new desktop, in hopes of getting better performance because I just cannot bear to uninstall any of my big mods.