I have  2 monitors connected to a GTX 560 running kmod-nvidia from the 
repositories v 310.40.

Thanks to help from people on the list it now uses RANDR and works well 
for everything tested except:

The monitors are both 1080p, arranged as a landscape on the left and 
portrait on the right. I switch the landscape monitor on an hdmi switch 
(I have to check but I think both monitors are in DVI connector on the 
board).

When I switch off this computer onto one of the other ones, something in 
the new setup crams everything onto the remaining monitor, which is not 
so bad but a) doesn't return to the old setup when I switch back and b) 
the pixel addressing is messed up so a click on an icon or menu doesn't 
do what's expected.

My solution is to click on the Application menu then use keyboard arrows 
to navigate to log out, log back in and everything works. Since some of 
you have kids who may be looking over your shoulder we'll call that 
sub-optimal.

So my questions are:

a) can I disable this too-smart for its own good feature?
b) Is there a way to reload the X config while running?
c) What else am I not so blissfully ignorant of about X configuration?

As always thanks for your help.

Joe