No, I'd say you're screwed in any OS (remember that
X servers can write directly to
hardware) Direct hardware access seems to be pretty standard in every OS, as writing through the kernel is too slow... Consequently, a really badly written video driver can vomit all over the
address space, and down the system goes.
BOOM!
More annoying are
video drivers that don't play nice. Quite a few video drivers (see
ATi,
Matrox) will happily attempt to bus-master to the card when its buffers are full, and let the
PCI hardware sort it out. This gives a 1% performance boost to the graphics card, and
hoses any PCI device trying to use the bus. Devices that send lots of little, time critical, packets (
sound card,
USB etc.) can't work when a graphics driver is doing this. USB
joysticks go too slowly to be usable, sound breaks up whenever a window is moved. Graphics card manufacturers
deny that this is their fault.
The
ATi Mobility 9x drivers do this. The workaround? Install
win2k. :(