I've just realised what you meant, Windows is silly for running its Windowing system in kernel mode while the UNIX X-window system runs in user mode.
Well I can see your point but Windows NT is a purely graphical OS, it doesn't have a text mode like UNIX does. When X crashes under Linux it's just as bad as it takes out all X programs ie OpenOffice so still I loose my work anyway, though this has only happened to me on Redhat 9.0 though.
Hmm. What about my Linux with nVidia graphics driver?
AFAIK, the nvidia x-subsystem is in two parts:
1) userland component, TLS links that make the
"nvidia" x-driver
2) kernel component, the 'nvidia' kernel module,
which is either modprobed when X starts, or manually
loaded before X.
So does this mean that the driver component actually
runs in "ring 0", while X-server
(and the nvidia's TLS component) itself runs in usermode?
And doesn't this make my Linux-box as unstable as
as the nvidia-kernel module is?