Unless you plan on having more than 4 GB of RAM in that computer, there is no reason to change to x86. I mean, you can, but you don't need to. Changing from a 32-Bit to a 64-Bit OS won't improve your speed. Add in another 2 GB of RAM, then change to a 64-Bit OS. Depending on your usage, a upgrade to 4 GB might make your PC faster.