How to i change from 32 bit to 64 bit on athlon x2 64 bit

[rearranged]

hi my computer runs on athlon X2 64 bit. it uses windows vista and at startup i had to chose which i wanted to use : 32 bit or 64 bit. i chose 32 bit and now i have programs that i can only use with 64 bit. i was wondering how to change to 64 bit. please help.

 

[megamanx00]

It's not like you can just switch it with a check box. You are going to have to re-install Vista, but this time you need to install the 64-bit version. The 64-bit version of Vista is a different OS than the 32-bit version of Vista.

 

[daship]

You need to reinstall 64 bit if thats what you like.

@ Megan man, some discs have both versions. 32 and 64.

 

[jitpublisher]

Be aware there is no direct upgrade from a 32 bit OS to a 64 bit OS.
You must do complete reinstall from scratch.