Firstly what a wonderful plane the 747-400 is and its such a shame I am suffering from this problem that has been re occuring so frequently. I am running XP with a fresh install and FS2004, PMDG 747-400, Active Sky, Ultimate Terrain and GE Pro. I always seem to have an out of memory error usually within about 10 miles of any airport and sometimes when I capture the ILS... I had 2 GB installed and put in another 2 taking the total to 4GB... windows XP only recognizes 3.2GB and when I have my error the memory has not gone over 1.3-1.4GB and the page file is around about 1.6GB yet there is over 1GB untouched memory.... I think it must be a software error within XP.... I am not sure if anyone has any suggestions as I am kind of out of ideas and it is such a shame not to be able to fly my favourite plane!!! (I wonder if I upgraded to Vista it would be the same)

Please check the PMDG Wiki and do a forum advanced search. This subject has been throughly discussed. I short, the out of memory is due to many issues, usually surrounding issues with third party scenery. Are you using any airport add-ons? If so, they can also exacerbate the problem.

>Firstly what a wonderful plane the 747-400 is and its such a>shame I am suffering from this problem that has been re>occuring so frequently. I am running XP with a fresh install>and FS2004, PMDG 747-400, Active Sky, Ultimate Terrain and GE>Pro. I always seem to have an out of memory error usually>within about 10 miles of any airport and sometimes when I>capture the ILS... I had 2 GB installed and put in another 2>taking the total to 4GB... windows XP only recognizes 3.2GB>and when I have my error the memory has not gone over>1.3-1.4GB and the page file is around about 1.6GB yet there is>over 1GB untouched memory.... I think it must be a software>error within XP.... I am not sure if anyone has any>suggestions as I am kind of out of ideas and it is such a>shame not to be able to fly my favourite plane!!! (I wonder if>I upgraded to Vista it would be the same)>>See the following thread. I believe UT is the main cause.http://forums.avsim.net/dcboard.php?az=sho...ing_type=search- John

What you may not realize about 32-bit Windows, is that a single process cannot access more than 2GB of RAM!! (3GB if the operating system is put into a special mode on startup) So, if you're only running a single application at a time, you will have 2GB (minus what is required by the operating system and background processes) that is completely unusable.Now, that said, you should never be getting out of memory problems with FS9 when you have 2GB or RAM available for it. See the other posts for more information.- Bill

Yeah once the drivers are up to snuff you should probably upgrade to Windows Vista 64 bit to take full advantage of that much RAM.