NVIDIA 190.18 beta for Solaris (GTX-280M) - Better, not perfect
I tried the 190.18 beta on a Boxx W2600 (rebadged Clevo D990F), which has a GTX-280M video adapter, using both Solaris 10 update 7 (905) and Solaris Express build 117. This release works much better. The system no longer crashes at the login screen and one can login and Gnome starts correctly. Under Solaris Express build 117 the display enhancements also work. The NVIDIA X Server Settings control also appears to work, sort of.
Issues I found seem to be when attaching an external display to the DVI port. It appears that when an external display is attached it mis-identifies which display is which. The LCD panel is automatically disabled and the external display is turned on at the 1920x1200 native resolution of the internal display. However, the NVIDIA X Server Settings control says the internal display is still active and the external display is disabled. It identifies the external display as DFP-0 (LPL) and the internal display as CRT-0. When I try to enable the internal display by selecting the disabled display it errors out.
It looks like something is cross-referenced in the driver.