If your computer is fairly new (within the last year or so), there is a good chance that you may have a 64-bit processor. For instance, the AMD Athlon 64 and AMD Opteron processors are 64-bit, as well as Intel’s older Pentium 4 with EM64T and Pentium D processors, and of course we can’t forget the Core 2 line-up.
You might be wondering, “What are the advantages of using 64-bit Windows?”
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You might be wondering, “What are the advantages of using 64-bit Windows?”
- Greater stability – Windows Vista 64-bit requires that all device drivers be signed.
- Access to more than 3.25 GB of RAM – if your computer has 4 GB of memory, you will be able to use all of it instead of being limited by the 32-bit memory addressing system.
- Performance – running a 64-bit operating system on a 64-bit processor offers better performance than a 32-bit operating system could provide.
- Backwards compatibility – most 32-bit applications work without an issue on 64-bit Windows, with the exception of Anti-Virus programs and some other system utilities that rely on drivers.
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Well, it's not that extreme, but it uses more RAM.

Do you know that Paint .NET which is available as native x64, gets 50-100% performance improvement when filtering calculations are performed. Damn damn!!!