Installing alternative Xdrivers

A beginner's X question:

We have a multiuser system here, with myself wanting to experiment with an
alternative Xdriver that I have pulled from the net. This situation eliminates
the possibility of my simply swapping the Xdrivers for a while, so I am trying
to decide upon a strategy which involves the least duplication of the exisiting
system. I expected to find that all of the display executables would involve
links to a nominated Xdriver, but the make files suggest this is not the case.
Where is the code that specifies the search path for the Xdriver?

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Conn V Copas
Loughborough University of Technology tel : +44 509 263171 ext 4164
Computer-Human Interaction Research Centre fax : +44 509 610815
Leicestershire LE11 3TU e-mail - (Janet):C.V.Copas@uk.ac.lut
G Britain (Internet):C.V.Copas@lut.ac.uk