For me, I'm sticking with 32 bit. My motherboard only supports 2gb of RAM max. The main reason to switch to 64 bit is to address more than 3gb of RAM. Also, I've read that some programs and drivers don't work in 64 bit mode. Sure, 64 bit OS's can run in 32 bit mode, but that slows your computer down. My processor supports both 32 and 64 bit OS's. I've decided to stick with 32 bit for compatibility reasons.