We don't purposefully restrict Second Life to certain drivers; it's just that our tech support
people aren't eager to advertise support for drivers that either are known buggy or that our
QA folks haven't had a chance to test. If there's a video card/driver combination that you
personally know work with the Second Life viewer despite not being advertised, let us know by
filing an bug report against our website here: http://jira.secondlife.com
The OpenGL support in the open source drivers is already known to be well behind the
proprietary drivers, sadly. Fortunately, the source code for the Second Life viewer is all
there for debugging/fixing purposes, and we'll gladly accept patches that fix the problem.