In our previous postm we've talked about the /3GB switch and its effect on system resources in previous posts. Today we are going to discuss how to determine whether or not /3GB is enabled on a 32-bit system without looking at the boot.ini file or using MSCONFIG.EXE. Finding out this information is not as difficult as you would think – there are actually multiple ways to find this information. We are going to find this information in three different ways – by looking in the registry, by using PSTAT.EXE and by looking at a Memory Dump File. So, without further delay, let’s look at the simplest of the three methods – finding the information in the registry.
To find the information in the Registry, all you have to do is look in the HKLMSYSTEMCurrentControlSetControl key, and examine the SystemStartOptions value. Below is the value from a Windows XP system that I have configured with /3GB.
As you can see, the ‘/’ character is removed from the string in the Registry, but the options themselves are determined easily enough. With this in mind, here’s a quick tip for Systems Administrators who might need to find this information for multiple systems – use a simple script or batch file to query this value in the registry on all your machines and write the output to a text file. Remember that you will need to be able to access the registry remotely for this to work!