Very similar problem here. I've played since launch on a Nvidia GeForce 6150SE nForce 430 and AMD Athlon II X2 220 processor 2.80 GHz. I have never experienced any lag or any kind of problems at all. I usually run the game on medium settings, and everything has been fine until the last update. Now, my graphics are so…
I'm talking with Support, so we'll see what happens. Before the Icewind Dale update, I never had a single problem with the game. No lag, no rubberbanding, nothing. It ran beautifully. Now, well... Edit: Tried to share a screen shot. Didn't work. Dunno why. Too tired to mess with it.