Can I install a 64 bit Windows 7 on a computer that currently has a 32 bit version of Vista? I think that my hardware can handle a 64 bit Operating System. I tried to install a 64 bit version of Windows 7 but the installation program checked my current Operating System and stopped.

Is there any way to override this?

How can I make sure my hardware can handle the 64 bit OS? (I build this computer from scratch)

I do not think this will delete my hard drive. Will it?

There is no upgrade path from 32bit windows vista to 64bit windows 7.
The only way is to do a clean install of the 64bit by booting from the win7 install dvd and selecting a custom install. This method will require you to backup all your data and re-install your programs.
You can find more info here:

Ok to find out if your motherboard will handle a 64bit OS, do this, go to this site and download cpuz it's a free utility that will tell all your motherboard specs and your computer for that matter.
also go to Device Doctor site that way you will get all your correct 64 bit drivers.

Also do what laser said, almost forgot. clean install only for it to work.

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