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Give Silent Hunter 4

A Memory Boost


This article is for people who are using Silent Hunter Wolves of the Pacific (Silent Hunter 4) in Windows 7 64-bit and have at least four gigabytes of memory (RAM).  It will show you how to edit the Silent Hunter 4 program executable file (sh4.exe) so Windows 7 knows it can handle more than two gigabytes of memory.  In geekspeak this is called making the executable Large Address Aware.

First, point your Web browser to the NT Core home page and click on the "Download the Explorer Suite" link.  There is a lot of information there about the software.  Once you have it saved, install it on your machine.

With that done, use Windows Explorer to navigate to the Silent Hunter 4 program executable file (sh4.exe).  By default it is installed in the Program Files (x86) directory, together with other 32-bit programs.  Look for the Ubisoft folder, and within that, the Silent Hunter Wolves of the Pacific folder.  You will find the file there.  Make a copy of the file and put it in another location.  In the event something goes wrong, you will have a backup.  Right-click the original file and select Properties.  You should see the following.

NOTE: the following images are thumbnails. Click them for larger images.


sh4.exe file with read only checked


Note that the "Read-only" box is checked.  Uncheck it, and then click Apply.  It should then look like the following.


sh4.exe file with read only unchecked


The reason we do this is so we can save the edit we will make to the file.

Next open the CFF Explorer which is in the Explorer Suite start menu program group.  Once it opens it should look like the following.


CF Explorer screen 1


Use the File menu to navigate to and open the sh4.exe file.  You should then see the following.


CF Explorer screen 2


On your left below "Nt Headers" you will see "File Header."  Click on File Header.  You should then see the following.


CF Explorer screen 3


On your right, highlighted in blue, you will see the words "Click here."  Do that and you should then see the following.


CF Explorer screen 4


In the box locate the line that says "App can handle > 2gb address space" and check the box next to that.  It should then look like the following.


CF Explorer screen 5


Click OK.  Next we need to save the edit.  You can use the File menu or the toolbar icon to save the edit.  You should see the following.


CF Explorer screen 6


You want to overwrite the original so click Yes.  That's it.  Henceforth Windows 7 will know that Silent 4 can handle more than two gigabytes of memory.  It will now access up to four gigabytes on a 64-bit operating system.  Don't forget to go back and check the Read-only box on your sh4.exe file.

If you are using Silent Hunter Wolves of the Pacific in 32-bit editions of Windows 7, Windows Vista, or Windows XP, the procedures used for editing the sh4.exe file with the CFF Explorer to make it Large Address Aware are the same.  Once done, Silent Hunter 4 can access up to three gigabytes of memory on these platforms.  However, if you have less than three gigabytes of RAM in your computer you should not use these procedures.  Also, in the 32-bit operating systems there are additional steps to perform.  You can perform these additional steps after you make the edit to the sh4.exe file with the CFF Explorer.  The additional steps increase the user memory settings.

From the Windows XP desktop right-click My Computer and then select Properties.  The System Properties dialog box will appear as follows.


Win XP screen 1


Click the Advanced tab and the following screen appears.


Win XP screen 2


In the Startup and Recovery section click on Settings and the following screen appears.


Win XP screen 3


In the System startup section click on Edit.  The Boot.ini file will open in Notepad as follows.


Win XP screen 4


You want to add "/3GB" after the switch that reads "NOEXECUTE=OPTIN".  After you make this edit the file should look as follows.


Win XP screen 5


Save the changes and close Notepad.  Click OK two times to close the open dialog boxes.  Restart the computer and the changes will be in effect.  Don't forget to go back and check the Read-only box on your sh4.exe file.

In Windows 7 and Windows Vista 32-bit versions go to Programs, Accessories, right-click on Command Prompt and select "Run as Administrator."  Enter the following text exactly as it appears at the command prompt and press enter.

bcdedit /set IncreaseUserVA 3072

Close the command prompt and restart the computer.  If you ever need to change the user limit back to two gigabytes, open the command prompt in the same manner and enter the following command:

bcdedit /set IncreaseUserVA 2048

Don't forget to go back and check the Read-only box on your sh4.exe file.

Download a PDF file with these instructions

Good luck and good hunting!