switch from Matrox G450 to GeForce 6200/6200TC

[Francois]

Hello,

I plan to change the graphic card I've run for years now, which is a Matrox 
G450  Dual Head (I don't use that feature though), to a GeForce 6200/6200TC 
from Twintech Graphics (6200 AGP, 256Mo DVI+TV DDR2)

What do I have to do to be sure I won't have any problem with that switch ?
Do I have to backup something first ? to download a driver (rpm but which 
one) ? to install something before the switch ?
Do I have to keep installed both graphic cards into the computer at least at 
the beginning ?
I run Fedora Core 6.
Thank you in advance. Francois
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