Hey Gary,
This actually has nothing to do with the Pagefile or Swapping or Physical Memory, it is a 32 bit OS issue. In fact the best thing you can do is to leave Virtual memory as System Managed. Ideally, you should not have the Pagefile and your OS on the some HDD as it could cause excessive paging. The best thing you can do is to use a separate HDD on a separate controller to your Pagefile altogether to really optimize your system if you are an ubergeek like myself...

With that being said this issue has nothing to do with any of that. I am willing to bet a lot of money that all of the users who are reporting OOM errors with FS9 or FSX or either:
A. Running a 32 Bit OS
B. Running a 64 Bit OS with FS9 without modifying the .exe to be largeaddressaware.
So you have 3 possible steps to fix the OOM error once and for all.1. Modify your FS9.exe to be largeaddressaware (FSX did this automatically after SP1)
2. Modify your 32 Bit OS's Boot.INI file to set the /3gb aware flag
3. Install a 64 Bit OS (The best move you will ever make as a simmer)
Regardless of going with 2 or 3 you will need to do number one...
For more information:
http://www.fsdeveloper.com/wiki/index.php?title=OOM_ErrorFor detailed instructions:The instructions below reference WinXP, Vista is different
The two steps are below.
Also do searches on the Avsim forum for "/3GB switch", "OOM", and "Memory" to learn more. And search google for "/3GB switch" and "/userva" and you'll find the Microsoft technet pages all of this in nauseating detail.
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STEP 1 -
Here's how to enable the 3GB switch (Copied from Michael Swannick):
Adding the 3GB switch is very simple. You first need to locate your machines Boot.ini file which should be located in the root of your main system drive. (Be aware that this file may be hidden and marked as read-only initially.) You will want to open this file in a program such as Notepad to edit it properly.
To safely add the 3GB switch we recommend adding a second instance of the OS in the boot.ini, and add the /3GB switch to that second version.
----- default boot.ini without 3GB Switch -----
This is what a default boot.ini file will look like. (This may differ from system to system.)
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Pro"
----- updated boot.ini with 3GB Switch -----
This is what the updated version should look like. Notice the /3GB that has been added to the second instance of the OS line.
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Pro"
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Pro with /3GB" /3GB
And if you have a 512MB or greater video card, you'll need to add the /Userva=?

also. I have a 512MB card, and 2900 works for me so:
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Pro with /3GB" /3GB /Userva=2900
256MB /userva=3072 (ie, 3GB)
512MB /userva=2816
768MB /userva=2560
1024MB /userva=2304
Once you have updated your boot.ini file accordingly and have saved the changes, simply restart your system for the changes to take affect. When your system reboots you will be given the option to choose either the standard Windows XP version or the 3GB switch enabled Windows XP version. If you choose the 3GB version and it fails to allow Windows to properly load, just restart your system and you will be given the two options once again, where you can then choose the standard Windows XP version to load. Either way, if it works or doesn't, you can then remove whatever line you don't need in the boot.ini file. Alternately, you may wish to leave both settings so that you can choose to boot without the 3GB switch should you ever have problems with drivers installed in the future. The boot loader will default to the first option listed in the file. So you may want to put the /3GB option first. You may also wish to lower the timeout value to something quicker so that you don't have to wait for 30 seconds or press enter with each boot.
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STEP 2 -
Now to modify to the fs9.exe (thanks to Markus and Stu):
Try this only if you have at least 2 GByte of RAM and at your own risk.
First download the explorer from
http://www.ntcore.com/exsuite.phpNext make a copy from fs9.exe. Than start "CFF Explorer" and open the orginal fsx.exe file.
Now go to NT Header/File Header and click File Header. Ther you find a button labeld "click here". Click it. And select the mark at "App can handle> 2gb adressest "
Save the modified EXE, overwrite the orginal one (You have youre copy saved?).
Following the above procedures will fix the OOM error on 32 bit OS's as a band aid as I stated above but to REALLY REALLY CURE the ROOT CAUSE You sill still need to do step number 2, but you don't have to worry about ANY of the Boot.ini garbage and your machine can now see and use more memory more efficiently...
32 bit OS's are dead...
Tada

Paul Solk