This also sounds much like bug 3731, which many people have reported. I don't know if it's driver-specific, but the problem can be traced down to xresprobe, which is not reporting the resolutions correctly.
Also, xresprobe is not installed by default on Feisty, so I wonder if people who upgrade from Edgy->Feisty might be losing xresprobe, and then when x reconfigures it misses the refresh rates? Or else perhaps xresprobe is unable to interpret the EDID data from these nvidia cards?
This also sounds much like bug 3731, which many people have reported. I don't know if it's driver-specific, but the problem can be traced down to xresprobe, which is not reporting the resolutions correctly.
Also, xresprobe is not installed by default on Feisty, so I wonder if people who upgrade from Edgy->Feisty might be losing xresprobe, and then when x reconfigures it misses the refresh rates? Or else perhaps xresprobe is unable to interpret the EDID data from these nvidia cards?