XP Pro 64-bit OS...what drivers/games work and what don't?

well, the title says it all. I'm thinking of going 64-bit with my next system, but I'm not sure if the driver hassle and trying to figure 5.1 sound switching to new card will be worth it. And then there's the which games will work and which won't issue (UT/UT2004/UT3/Q3/Q4/Doom3/Painkiller/Postal2/etc.)? Anything anoyone knows will be appreciated. I do know about the PlanetAMD64 site and the info there though. Thank you.
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