Please note that Paint.NET uses your hard drive to store temporary files related to undo/redo. Actual disk space requirements will depend on the type of actions you perform on an image, and on the size of the image. These temporary files will be compressed if you are using the NTFS file system. Compression results in less disk space being required, and improved performance due to less hard drive activity.
Some systems have special attributes that change the way Paint.NET works or performs:
Paint.NET will automatically take advantage of Jump Lists, Aero, Glass, and DirectWrite. Jump Lists provide quick access to the File → Open Recent list by right-clicking on the Paint.NET icon in the taskbar (Windows 7 only). Aero and Glass provide a refreshed and richer user interface style/theme. DirectWrite is a new system component that provides font management and text rendering at higher quality and with better performance compared to GDI or GDI+. If you are using Windows 7, or have installed DirectX 11 for Windows Vista, then DirectWrite will automatically be used. Otherwise, the Text Tool will use GDl.
Paint.NET is heavily optimized for systems with multiple processors and/or multiple cores. These systems include (but are not limited to) those with Intel Core 2, Intel Xeon, Intel Pentium D, AMD Opteron, and AMD Athlon 64 X2 processors. Dramatic performance increases over single core and single processor systems are possible.
Since version 2.6, Paint.NET has had full, native support for 64-bit processors. Benefits of 64-bit mode include better performance and the ability to work with larger images or multiple images. This support requires that you have both a 64-bit capable processor and a 64-bit operating system installed. An example would be an Intel Core 2 Duo processor with a 64-bit version of Windows 7.
You do not need to perform any additional configuration steps to enable 64-bit mode: as long as both your processor and operating system are 64-bit capable, Paint.NET will automatically run in 64-bit mode.