Comment 28 for bug 526892

>> @Scott: Would it be possible to tell plymouth to use nouveau and then
>> have X use nvidia? Or is it one or the other from the moment you boot?
> It's one or the other.

How is this determined? Does nvidia-current get used, when installed, otherwise nouveau gets tried?

The last time I've tried nvidia-current it failed with the screen turning off (but booting fine otherwise) (bug 534634).
nouveau apparently does not get used (although I can "modprobe nouveau"), and it cannot get loaded in X, too (bug 533642).