A 64-bit PC is faster at handling data in the computer's memory, because it processes 64 bits of data at time, as opposed to the more common 32-bit PC. However, the benefits are only easily seen if your computer has at least 4 gigabytes (GB) of random access memory (RAM). If you run many programs at a time, upgrading from 32-bit to 64-bit can be very beneficial.
While most programs made for 32-bit PCs will work fine on 64-bit PCs, there are some important exceptions. If you decide to upgrade, you will most likely have to get new anti-virus software. Also, hardware drivers made for 32-bit PCs will not work on a 64-bit PC. Before committing to an upgrade, be sure that there are 64-bit drivers for your printer or any other device. Information regarding drivers can be found on the website of the device's manufacturer. Once you are sure you will not run into any compatibility issues, you can go ahead and purchase a 64-bit version of Windows Vista on DVD.
Before upgrading, remember to back up any files you want to keep to either DVDs or an external hard drive. Changing to 64-bit Vista will wipe your computer clean, and anything you do not back up will be lost forever. Once your files are safe, place the Vista install DVD into your DVD drive. Restart your computer, and then choose to start Windows Vista setup. Follow instructions given, and select "Install Now." You should also get the latest installation updates when asked. Enter your product key, which can be found inside the Windows package you purchased. Accept the license terms, and select a custom type of installation. Select where you wish to install Windows, and then click "Next." Follow any further instructions to finish installation.
Once you have finished installation of 64-bit Windows Vista, the very first thing you should do is install anti-virus software. You need your computer to be secure before you move your private files back onto it. After installing an anti-virus program, you can download and install drivers for your devices from the manufacturers' websites. When this is complete, copy your old files back onto your computer and install any of the programs you wish to use. If you happen to encounter any problems with 64-bit Windows Vista, refer to the Microsoft website, where there is an abundance of help and information.