I am having problems in the Imperial City Market District, in that it lags. BADLY. It's weird because I have no problems with anywhere else I've been, just this one cell. I've tried PCB, but that didn't do anything. Anyone else encounter this and have a suggestion?

The IC market district usually has a lot of NPCs wandering around so it might be that causing the slowdown (a lot of scripts to process etc for that many NPCs) - try lowering the actor fade distance and see if that helps things (this will lower the distance at which actors come into view and also relieve some of the script processing)

Turns out it was actually a mod that was respawning already open crates everytime I entered the Market District, so it was because there were LOTS of crates. I've disable the mod. Thanks for your help.