I can't say for sure at 1920x1200 I'm afraid, as I've never used that resolution, but my 3870GX2 is pretty much exactly as fast as the 8800GTX I had so I would think your 8800Ultra would be a bit faster maybe.So my what your saying then is my 8800 Ultra which can force 1900x1200 res with 8X AA and all the bells and whitles is better than a 3870X2 ?
The only exemption I can think of off the top of my head is Oblivion, it loves ATI cards.