If your computer Operating System (OS) is  Windows Vista, and you use virtualisation for development purposes (e.g. SharePoint solutions), then the following tips and tricks will help you boost overall computer performance:

1. Add more RAM to the computer. Obviously the more RAM you have, the faster the performance becomes. For running a basic Windows Server 2003 image with SQL Server 2005 and SharePoint Services (WSS or MOSS), I recommend at least 768 MB of RAM for the image, and at least 768 MB for your host OS (Windows Vista). I recently upgraded my work laptop from 2 to 3GB and could immediately notice the extra performance.
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2. Enable Virtualization in the host computer BIOS. If you use a DELL notebook, press F2 to get into the BIOS when the computer restarts. Navigate to POST Behavior  > Virtualization, and enable virtualisation.
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3. Run image from a different hard drive.  For example, a portable hard drive
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4. Disable unnecessary visual effects. Right click on My Computer, then select Properties. Click Advanced system On the System Properties window, click tab Advanced, and Performance Settings.
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   In the Visual Effects tab, select Adjust for best performance.
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   Also change the desktop wallpaper by selecting a solid colour.
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5. Disable unnecessary services. Open the Services console (Start > Run… > [Type in "services.msc"]. Disable the following services:

• Superfetch - though marketed as “Maintains and improves system performance over time.”, it seems to do the opposite
• Themes – this will disable Windows Vista themes