Every single system I have updated has been amd machines and havent had a single one fail yet. The ones that have been failing have been the nvidia ones, and it is driver related.
This is the problem with every new OS, the lack of good drivers, happened with vista and 7 as well.
So you could just uninstall the nvidia drivers and install 10 and then grab the newest drivers for 10, or you can try updating them first.
Personally I always remove anything that can cause a problem, so if I have a crap driver I will just remove it and worry about putting new drivers on it after the upgrade
Shane