installing Win 7 from Vista

I have Win Vista 32 bit system and I want to know if I can install Win 7 64 bit system without doing the so called "clean install". I know if I go from my 32 bit to Win 7 32 bit is a very seamless upgrade, but the change to 64 bit is confusing for me. Thanks!!

You cannot upgrade from a 32-bit installation to a 64-bit installation without doing a clean install. This is probably due to the fact that things are organized slightly differently on the 64-bit version of Windows (it has two Program Files folders, etc.). Here's a guide to the types of upgrades that can be done:

No. If you upgrade, you will have to do a full format and install.

Check into Windows "Easy Transfer" to help ease the pain.

This post by Scott Hanselman details more about the process and options.

You are going to need to reformat to change OS from 32-bit to 64-bit. The differences in the Architecture make it so that an upgrade is really hard if not impossible.