Upgrading from 32 bit to 64 bit

[TheFailGamer]

The copy of windows 7 I had was 32 bit and I realized i had 8GB ram and a decent cpu.
I might get the 64 bit disk but how would i go on installing it? Would I have to erase everything in my harddrive or when I put the disk in would it do it for me?

 

[manofchalk]

Yup, only way to upgrade from 32bit to 64bit is a complete OS install, which basically means you will have to format the drive and lose whats on there. Copy your data over to a secondary HDD if you want to keep it.
You should have the option to format the drive when running off the the Windows disc.

 

[neieus]

In the mean while you could always enable Physical Address extension to take advantage of your extended RAM. You can do this on Windows 7 by opening a command window and enter the following:

BCDEdit /set PAE ForceEnable

A reboot will be required before the changes will take effect.

 

[Dark Lord of Tech]

You need to perform a clean install with format:

To install Windows 7 using the Custom option and formatting the hard disk

To format your hard disk during Windows 7 installation, you'll need to start, or boot, your computer using the Windows 7 installation disc or USB flash drive.

Turn on your computer so that Windows starts normally, insert the Windows 7 installation disc or USB flash drive, and then shut down your computer.

Restart your computer.

Press any key when prompted, and then follow the instructions that appear.

On the Install Windows page, enter your language and other preferences, and then click Next.

If the Install Windows page doesn't appear, and you're not asked to press any key, you might need to change some system settings. To learn how to do this, see Start your computer from a Windows 7 installation disc or USB flash drive.

On the Please read the license terms page, if you accept the license terms, click I accept the license terms, and then click Next.

On the Which type of installation do you want? page, click Custom.

On the Where do you want to install Windows? page, click Drive options (advanced).

Click the partition that you want to change, click the formatting option you want to perform, and then follow the instructions.

When you've finished formatting, click Next.

Follow the instructions to finish installing Windows 7, which include naming your computer and setting up an initial user account.

http://windows.microsoft.com/en-us/windows7/installing-and-reinstalling-windows-7