3GB Enabler Fix for Windows Vista & 7
The 3GB enabler is an awesome utility that has a magic tendency to fix one of the last remaining outstanding of Sid Meiers Railroads instability. While the process could hardly be much simpler with the script there is one rather nasty reliance; for 32bit versions of windows you need to manually tell windows to allow 3GB enabler to work. Traditionally this was done by use the 3GB switch in boot.ini. Unfortunately Windows Vista and 7 no longer use the boot.ini, but don’t worry users of Vista & 7 32bit, Microsoft didn’t leave you high and dry.
I came across the solution after Sam brought the quandary to my attention. The solution is actually quite simple, go to the start menu and in the search box type ‘cmd’, don’t hit enter. Wait until ‘cmd.exe.’ appears on the menu and then right click and select “run as administrator”. Then run this command:
BCDEDIT.EXE /Set IncreaseUserVa 2900
You can copy and paste that into the command prompt by using the right click menu, keyboard shortcuts CTRL+C and CTRL+V don’t work in the command line. Then restart for the changes to take effect.
Once you have done this and used the 3GB Enabler you should be able to play Sid Meiers Railroads crash free, so have fun and watch what time it is.
Note: Users of 64bit OSes don’t need to do this step and can use the 3GB enabler directly.


I think I have a 32-bit processor because under the performance tab it says 32-bit (highest) but it will not allow me to “run as administrator because there are no compatibility issues. Help please.
Could you upload a screenshot somewhere? I haven’t encountered that problem before and if you show me what you are doing I can likely spot whats wrong.
Oh wait, “32-bit (highest)” is what is shown on for the dropdown list for selecting the amount of colours you want to use, ie 16-bit colour 8-bit colour or 32-bit colour. This is not what I meant by 32bit vs 64bit. 64bit is the type of processor and version of the OS.
With that said you do have a 32bit version of Windows.