[Newbie]Which dual headed video card for production machines?

[newbie@XFree86.Org (Dan Garthwaite)]

We are currently having Xserver crashes with both Matrox G400 and G450's
using XFree86 4.2.0 on stock RH71 machines ( plus XF4.2.0, of course ).

ARE there any dual headed AGP video cards that can be reasonably guaranteed
not to have any problems?  I prefer to stay away from any proprietary
drivers.

  -Dan Garthwaite