CAM on 64-bit Microsoft Windows


Note: 3D graphing is no longer available in the CAM download due to stability problems.

The instructions on this page only apply if you have a 64-bit version of Microsoft Windows (how to tell).

When using CAM on 64 bit windows, you have the option of using either 32-bit or 64-bit Java:

  • 32-bit Java is limited to running CAM with up to 1.6Gb of RAM, but supports Java3D (used by CAM for 3D graphing).
  • 64-bit Java supports running CAM with more than 1.6Gb of RAM (useful for large simulation data sets) but does not support Java3D. 3D graphing will not be available.

It is possible to install both 32-bit and 64-bit Java on the same machine, and to choose which version to use by selecting the appropriate .bat file each time you start CAM. This is explained below.

How to install the different versions of Java:

If you visit the Java download site with any browser except 64-bit Internet Explorer, you will only be presented with the option to download 32-bit Java.

To get the 64-bit version of Java, either use 64-bit Internet Explorer or visit this page (with any browser), click on the link to download the latest version of the JRE (Java Runtime Environment), and on the next page manually select the version for the "Windows x64".

 Once you have installed both versions of Java (and restarted your computer if prompted), you should be able to run CAM in either 32 or 64 bit mode by following the instructions given below.

How to start CAM on 64 bit windows. This depends on which version of Java you wish to use:

  • 32 bit Java: double-click  CAM_java32_on_windows64.bat (to run 32-bit Java with 1Gb RAM - Java3D capable).
  • 64 bit Java: double-click CAM_java64_on_windows64.bat (to run 64-bit Java in 64-bit mode with 6Gb RAM - NOT Java3D capable).

 Some notes:

  1. If you do not have these startup scripts in your CAM directory, download the latest version of CAM.
  2. If you try to use a startup script which is incompatible with your installation - eg. if you use CAM_java64_on_windows64.bat on a machine without Java 64 installed - CAM will not start.
  3. If you try to use a startup script which requires more memory than you have on your machine, CAM will not start. For more information on memory usage in CAM and how to change the 1Gb or 6Gb limits mentioned above, see Memory configuration in CAM)

Why *not* to start CAM on 64 bit windows using CAM.bat

Starting CAM using "CAM.bat" will try to use 64-bit Java. However, depending on how you installed Java, you may only have the 32-bit version, in which case CAM will not start using this method (you may see a command prompt window flash briefly on the screen). Even if you do have 64-bit Java installed, "CAM.bat" will run CAM using 64-bit Java (i.e. no 3D graphing) in 32-bit mode (i.e. only 1Gb RAM) - the worst of both worlds!

See also the 64-bit vs 32-bit FAQ page on