Windows 7: Will clean install of 64 bit make files on another drive incompatible?

I'm currently doing a clean install of windows 7 64 bit on my 32 bit XP computer, I used the upgrade advisor beforehand and it said a lot of my programs where 64 bit compatable, and a large chunk of them are on my other hard drive (the one im not installing windows 7 on). After the install is finished will they be useable or will I have to reinstall them?

Also sorry that the thread title doesn't completely say what my problem is...Theres a character limit...

You have to re-install them cause your Program files (x86) folder will also be modified in your System Drive, by system drive i mean "where the OS is actually installed"...