Re: NVIDIA 185.18.36 lock on Dell XPS m1730
I do not believe the README is inaccurate in this regard: SLI on notebooks is not officially supported by the NVIDIA Linux graphics driver; however, it is not explicitly disabled, either.
That said, I was able to track down a Dell M1730 with dual GeForce 8700 GT GPUs today. It reproduces the behavior described in this thread: 180.52 works with SLI enabled, 190.42 yields a system hang. It looks like this problem is fixed in the upcoming 195.xx driver series.